This story was written for the Poly Big Bang.

The timeline's a bit off in this fic – Harry is a few years younger than he should be, and the events of Arkham City take place over a few more days – but go with it. And while the general plot of Arkham City is the same, Harry's presence changes a few things.

Warnings - Het and slash sex, dub-con, Stockholm Syndrome, minor character death.

X

"It's a brilliant opportunity; I'd advise you to take it," Gawain Robards smiled, his lips stretched wide in a possible attempt to dazzle Harry with his sparkling white teeth so he'd accept the offer.

It was a good opportunity, Harry agreed.

The American Ministry of Magic had got in touch with the British Auror Department, requesting Harry especially for assistance with an assignment. It would be an undercover mission based in a Muggle prison in America, for a period of at least three months. Apparently the prison had a lot of violent gangs within it, and pairs of Aurors were going to infiltrate each gang to report any findings or weaknesses.

Robards hadn't yet given Harry more details than that, which was what made Harry reluctant. Lengthy undercover missions were reserved for the more skilled and experienced Aurors, and being requested for one - an international one, no less - should have been an honour.

Harry just wanted to know why the American Ministry wanted Harry's help in a Muggle setting, of all places.

"A Muggle prison?" Harry queried, relaying his thoughts to Robards. "Why do they want me for a Muggle prison?"

Robards cheeks flushed slightly, but he held Harry's gaze with confidence. "This prison is unlike any other. The Muggles dreamt it up, but they soon lost control over it. The Auror Department in America is heavily linked to a Muggle organisation called the FBI. Only one or two seniors are aware of the magical element; however the Aurors have assisted in numerous Muggle cases nonetheless. A police commissioner named Jim Gordon from Gotham city, where the prison is based, had sent his own undercover officers in, but has requested back-up. He was offered the Aurors."

"So there's going to be a team?" Harry asked, blinking. He just still couldn't fathom why they needed him as well. Robards nodded at his question, and Harry tilted his head thoughtfully. "So why do they need me? I'm sure the Auror Department over there is large enough to have enough involved."

"Why wouldn't they want you?" Robards cried, throwing his hands in the air. "You're the Boy-Who-Lived! You defeated the Darkest wizard in history at the mere age of seventeen."

Harry held back his groan, not wanting to show his boss any disrespect. Although he had never been able to escape his fame, Harry sincerely doubted that was the only reason they wanted him; it had been nine years since the end of the war, and the novelty of Harry Potter had worn off for most people.

"You're also a very competent Auror, considering your age," Robards continued, surveying Harry with a proud smile. "Trust me when I say they need the best. A lot of the American Aurors did not wish to go undercover in this prison, and out of those who did, all but one refused to go undercover with the Joker."

Robards slid a Muggle photograph over to Harry, showing a picture of a man with paper white skin, bright green hair, and lips painted with red which curved up onto his cheeks, giving him a permanent smile. Despite the clown like appearance, the man's green eyes were cold and threatening, and the painted smile only served to make him creepy rather than funny. Harry could see already why the Aurors didn't want to get close to him.

"Oh," was all Harry could say, but Robards nodded in understanding.

"The Joker is a very dangerous man, but also very important. In the hierarchy of the gangs, his is very much at the top, and a lot of the violence is caused both by him, and by others who are desperate to claim his spot," Robards expanded, sliding the photograph back towards him. "He is intelligent, remorseless, and quite frankly psychotic, and they can't send one Auror alone. They chose you, Harry, because you know what it's like dealing with somebody like that. Of course, a mission like this will benefit you greatly in terms of employment; as you may know, I am planning to retire soon, and this would definitely push to the front line of becoming next Head Auror."

Robards didn't need to try and bribe Harry in a roundabout way; he had already made up his mind.

From what Harry could tell, the Joker was ruthless and dangerous, and a risk to numerous Muggles. Going undercover was dangerous, and if his cover was blown, Harry's head would most likely be next to go.

"I'll do it."

X

Valerius Erkens was a tall, muscular man who made Harry feel tiny.

Erkens was Harry's new Auror partner, and had at least thirty years on him, which was perhaps why the man didn't seem overly impressed when he first met Harry.

"I thought you'd be older," Erkens had said as way of greeting, and hadn't really spoken much since.

Matilda Duke, the American Head Auror, made up for Erkens' lack of talking. She was a dark-skinned woman with stern eyes but a caring smile, and she had provided Harry with a lot more information than Robards had.

The prison was called Arkham City, and was literally a walled in part of Gotham. The concept allowed for a greater number of prisoners, and Blackgate Prison and Arkham Asylum for the Criminally Insane – the main criminal holding facilities before the new build - had emptied their inmates into the city, along with prisoners from smaller jails in the county.

Of course, the higher number of prisoners combined with the city layout meant that the Muggles soon lost control, and undercover Aurors and cops were needed to find out who exactly was running what, and how much of a danger they posed to the public who lived just outside the walls.

Duke had been unable to tell Harry much about the Joker, and instead just re-emphasised how dangerous he was. She had been able to tell Harry that the Joker had a partner named Harley Quinn, and she was almost as dangerous as Joker herself. Duke also mentioned a costumed vigilante who called himself Batman was a major crime fighter in the city but he refused to kill, so Harry wasn't to break cover if Batman targeted them while undercover.

Duke had made Harry feel more confident about what he was getting into, but the worried looks from the other Aurors soon made him lose it again. Surely one man couldn't be that dangerous?

Harry knew that was a lie.

But the Joker was a Muggle, and though Harry wasn't permitted to overtly use magic, he would have his wand on him at all times, and the knowledge made him feel distinctly safer.

It was when they were making their final preparations that Erkens finally spoke again.

"Do you really think you can handle this?" Erkens said out of nowhere, making Harry jump. "A kid like you is just going to get lost in the walls of Arkham City."

"I am not a kid," Harry hissed, feeling quite affronted; he was twenty six, not twelve! "Duke wanted me because everyone else was too scared to do it."

"Bravery isn't the only thing you need to be suited to the job," Erkens muttered with a scowl that wasn't quite aimed at Harry. "Duke wanted you because of what you did with that Voldemort fellow, and I admit, defeating a Dark Lord at such a young age was impressive, but that one act doesn't automatically make you a better Auror than the rest. There's plenty they could have chosen from who have years of experience."

"Well I'm here and they're not," Harry stated, looking at Erkens pointedly. "Just because I'm younger and don't have as many years of experience doesn't mean I'm not skilled. I'm a damn good Auror, and a good partner, and I expect you to watch my back like I'll watch yours."

"Seriously, kid, calm down," Erkens laughed, holding his hands up and making Harry frown in confusion at the sudden switch of mood. "I'm not saying all this because I don't want you with me; I just don't want it on my conscience if you go walking into Arkham unprepared and get yourself killed. Hell, being killed might be the least of your worries; did you hear about Harley Quinn? She was the Joker's psychiatrist at one point, and thought she could handle him. Now she's just as psychotic as he is."

"Well I appreciate your concern, Valerius," Harry said, forcing himself to smile at the irritating man. "But I'll be fine."

X

Arkham City was different from anything else Harry had imagined.

It had been described as a walled off part of the city, but it was so much more than that.

Tall, dark buildings lined the streets, all of them with smashed windows and graffiti scrawled across the walls. The roads were dirty and damaged, and rough beneath Harry's feet, but he ignored the pain as he traipsed after Erkens, drawing his coat closer around himself.

It was only November but it was freezing cold, with flecks of snow drifting slowly through the wind. The walls around Arkham were monstrous; reaching high above the rooftops but close enough that any of the prisoners who looked would see the shining silver spikes sticking out threateningly at the top. Harry wondered if those walls were keeping the heat out, because this cold was just unnatural.

Harry had met the other Aurors briefly before they came to Arkham, discussing their final plans. They weren't to meet each other while inside the walls, but they were permitted to throw up red sparks in a life-threatening emergency. After a while, Harry zoned out of the discussion, only to be drawn back in by the names the Aurors were mentioning; Penguin, Two-Face, Riddler – just what sort of people were in this place?

Harry and Erkens didn't have to worry about any of the other oddly-named criminals though; the Joker was their only concern, but despite his more comedic name, the other Aurors shuddered at the mention of it, much the same way witches and wizards in Britain still did whenever anybody said Voldemort.

They had Apparated into an empty building in Arkham City at different times, and now Erkens was leading Harry to the Industrial District where the Joker was rumoured to have set up base.

They had not yet run into anybody, but that was because Erkens was ensuring they didn't. Harry heard the voices, and he heard the occasional screams as men were beaten to a pulp, but nobody bothered them; not yet.

Night was starting to fall, the darkness washing over them quicker than normal; no doubt because of the looming walls and buildings that trapped them in. Harry was entirely innocent of any crime, yet being inside the prison walls was like a nightmare. The unconventional style of it all only seemed to make the feeling worse; while prison walls trapped criminals in, they knew they were in a prison anyway. The walls around Arkham City were trapping then literally within part of a city, and it was almost like a mocking hope of freedom.

"We should take cover somewhere for the night," Erkens muttered, stopping so suddenly that Harry almost walked into him. "Don't want to be out in this place after nightfall."

Harry couldn't help but agree.

Erkens said no more, but led Harry to a building somewhat smaller than the others. It was just as rundown as the rest of them, with boards in place of the glass in the windows and the door, and obscenities were scrawled in various colours of spray paint, some of them dated from before the walls ever went up around this part of Gotham.

"Gotham's a shithole," Erkens commented, noting where Harry was looking. "The only difference between Arkham and the rest of the city is that there isn't a wall stopping them from getting out."

Erkens cast a glance around them, and when satisfied they were alone, slid his wand from its holster up his sleeve and blasted the board in the doorway away.

"What are you doing?" Harry hissed in panic, twisting his head around as if he expected a crowd of Muggles to be standing there, gawping at them. "We're only meant to use magic in emergencies."

"There's nobody about," Erkens shrugged. "This place will be empty because nobody else could get into it, and if you'd rather take your chances somewhere else, well, I'll try and make sure your body gets sent home for a funeral."

Harry scowled but held back the urge to answer back, and he reluctantly followed Erkens into the darkness of the building.

Erkens cast Lumos Maxima to give them some light, and allowed them to see the inside of the building for the first time.

It looked like it had been some sort of office before the walls went up, with a doorway leading to an office, and another leading to a staff room with motivational posters on the wall. The sofas and chairs were worn and frayed, and the desk had every draw open with pieces of paper hanging out while others had fallen to the floor.

"I'll go and check the upstairs," Erkens told Harry, and he waved a hand towards the broken board. "Fix that back in place, and yes, you will have to use magic. Don't be so petty; a real Auror would know that the rules are never meant to be rigid."

Once again, Harry really had to fight against the urge to scream at Erkens, and instead nodded. Erkens flashed Harry a satisfied smirk before he headed upstairs, and Harry moved towards the doorframe.

He bent down, determined to fit the board back in place with nothing but his hands, but he rather underestimated the weight of the wood, and nearly buckled over with it.

Harry slowly dropped the board back onto the floor, and slipped his wand from his sleeve with a sigh.

He started to levitate the board up and back into place, the task now much easier. But then Harry cast his gaze onto the streets outside, and dropped the board in shock, the wood hitting the floor with an echoing bang.

A woman was standing on the street opposite, staring straight at him. Her hair was in pigtails, and she was standing with her hands on her hips. It was hard to make out any details in the rapidly falling darkness, but somehow Harry could just see the smirk on her face.

Harry jumped out of his skin when he heard footsteps behind him, and he span around and cast a Stinging Hex, blinking for a moment until he realised it was only Erkens there, grabbing his face and hissing in pain. Harry quickly relieved the hex and turned back around, but the woman was gone.

"What the Hell is wrong with you?" Erkens roared, slamming the board back into place with a wave of his wand. "I gave you one simple task-"

"There was a woman," Harry said hurriedly, still staring at the board as if he could see her through it. "I used magic and she saw it."

"A woman? There aren't many of them in here, and the ones that are in Arkham are up there with the worst of them; they have to be to survive here," Erkens mused, his voice now a lot softer. "So what if she saw you though? She's a dangerous criminal and probably insane; nobody is going to believe a word she says."

Harry couldn't shake the feeling of dread off him though.

He struggled to sleep that night, lying on a rough sofa with his legs hanging over an arm, shivering with cold despite the Heating Charm Erkens cast on the room.

Harry had never pictured Arkham City to be a lovely place, but in only a matter of hours it had proved to be a living nightmare. It was nothing but a desolate land, filled with crime and violence. Luckily Harry hadn't had to see that side of the prison yet, but his and Erkens' destination was right in the middle of a gang war, if that was even the right word for it.

Eventually, when Harry could no longer fight his tiredness, sleep washed over Harry, and he dreamt more vividly than he had in a long time.

He dreamt of a pig-tailed girl in a frilly dress standing over Erkens and plunging a knife into his body again and again, smiling as blood splattered over her dress and onto her face. He dreamt of a man in the background cackling, clapping his hands with glee as he watched the scene. The man then drew his own knife and dug it into his own face, cutting the lines that formed a painted smile. Manic green eyes then turned to Harry who was tied to a bed, and the Joker smiled widely, caressing his knife as he whispered "you're next."

X

They were being followed.

Harry and Erkens both knew it, but they ignored the person for now, waiting to see what their goal was.

Harry suspected it to be the woman from the day before; he kept on getting glimpses of blonde pigtails, and flashes of red and black.

Part of Harry thought she was planning to hunt him down and burn him on a makeshift stake for practising witchcraft, and he had to shake his head to rid himself of those thoughts. He didn't know what it was, but just being inside the walls of Arkham City seemed to make everything more gloomy and daunting. Even the winter sun was being blocked out by the massive walls, with only a few streams filtering through and casting dark shadows on the ground through the gaps in the buildings.

The day seemed even colder than the one before, but his freezing skin was still no distraction from their stalker.

"What are we going to do?" Harry whispered, just loud enough for Erkens to hear him.

"Nothing," Erkens answered bluntly with a shrug. "If she's who I think she is, she may well be our key to the Joker's lair. Remember that's what we're here for, and any way in is good enough for me."

A shiver ran down Harry's spine, and had nothing to do with the cold.

"You think it's that Harley Quinn girl?" he asked, his voice lowering even more.

Erkens nodded, and Harry cast the man an uncomfortable look. The dream from last night still stood out vividly in his mind, and he suppose now that the woman who had been brutally slaughtering Erkens was Harley Quinn. It wasn't like Harry was a Seer or anything, and he had always been one for strange dreams, but he still couldn't shake the images from his mind.

It was strange really, being so cautious of Muggles. Harry had always been confident in his Auror work, and wasn't afraid to take on any witch or wizard, no matter how dangerous, but the thought of the mysterious Joker and Harley Quinn was giving him the twisted stomach he last experienced on his very first Auror case.

He hadn't even been that bothered by the thought of it until he was actually in Arkham City, and Harry wondered if there were Dementors hiding in the walls, sucking out enough happiness and sunlight that the people inside couldn't help but feel anything but doom.

"The Industrial District isn't far now," Erkens murmured, the pace of his walking picking up as they started to get away from the closed in buildings and more into open space. Even with the buildings spread out more, the walls were still close-by, towering over them threateningly.

As they walked on, stone buildings turned into metal, and cranes and uncompleted frameworks were dotted about, and abandoned boats were stuck in the icy water. The people who had built the wall had allowed part of a river to stay inside the walls, most likely to give prisoners false hope of escape.

Despite being so close to where they needed to be, the journey was taking them ages with the almost constant need to be ducking behind corners and sneaking past thuggish looking inmates. The woman was still following them, and she seemed to know the area well; sometimes appearing for fleeting moments in front of them, and other times at the sides.

"We need to be at the steel mill," Erkens said, pointing towards some towers and chimneys just ahead of them. "The Joker himself hasn't been seen for weeks, but his lackeys seem to hang out there."

Harry nodded, and they resumed their walk, the only sounds that of their feet crunching on the thin layer of ice on the ground.

"Any plans for getting inside?" Harry asked, still quite unbelieving as to just how much they were unprepared for this, despite Robards and Duke insisting they had prepared as much as they could.

"Apparently the Joker is always inviting people to join his gang," Erkens answered confidently. "We just have to find out where the auditions are."

"Well isn't this your lucky day, boys?" a female voice spoke, and Harry froze as he heard the clicking of guns from all around them.

The woman who had been stalking them finally appeared in front of them fully for the first time, her appearance taking Harry aback slightly. She was tall and slender but with feminine curves, and dressed in an outfit that mismatched red and black. Leather clung to each leg, one side red and the other black, with alternated coloured boots that reached past her knees. She wore a red and black corset which revealed her midriff, and fingerless gloves reaching up to her elbows, once again with one side red and the other black. Even her blond pigtails with dyed at the tips with one colour at each side. Her face was painted white, with rich red lipstick on her lips and black circles around her eyes.

She looked to be a similar age to Harry, and it was that, combined with non-threatening frame, that made the woman's danger seem more real. Harry would never have looked at her and thought she was vicious criminal, and it was only his prior knowledge of the sort of people who were imprisoned in Arkham City that alerted him to it. If anything, had they met in the streets or at a club, Harry would have found himself rather taken by her; in fact, knowing she was dangerous didn't decrease her attractiveness at all.

"I'm Harley; Harley Quinn," the woman introduced herself, and Erkens nodded, having suspected Harley to be the one following them all along.

Harley clicked her fingers and a circle of men came out from the shadows, their guns pointed warningly at Harry and Erkens. Harry curled his fingers gently over the tip of his wand, ready to bring out in a flash if he needed it. The men from the shadows were bulky and covered in tattoos, and they each wore a clown mask with a black painted smile and a shiny red nose.

There was no way Harry and Erkens could take on all of those men without the risk of at least one of them ending up shot, but if the danger got too much they could simply Apparate if they needed to. Their mission really depended on them getting to the Joker's lair, however, so Apparating too soon could destroy their mission completely.

"So you wanna see Joker, do ya?" Harley pressed on, filling the otherwise daunting silence. "Boys, you take the old guy; I wanna have a little chat with Green Eyes."

Erkens threw Harry a look that plainly said 'go along with this for the sake of the mission'.

So Harry let the thugs grab hold of Erkens by the shoulders and steer him away, and with one quick look at Harley, Harry felt somewhat envious of Erkens being taken by a group of large men. Thugs were commonplace and easy to handle, Muggle or not, but Harley Quinn was a whole other story.

Her blue eyes were glittering but devious, contrasting with the child-like smile that she had on her face. The combination made Harley almost impossible to read, and Harry couldn't help but wonder just how she came to be that way.

"So, Green Eyes," Harley sang, circling Harry like a bird of prey. "Where do you keep your magic wand?"

Harry froze, his fingers tightening around the object Harley was referring to.

"My name is Harry," he said, watching every movement Harley made. "And I don't know what you're talking about."

He didn't know whether or not it was worth lying about magic; Harley had seen it already, but Harry didn't know how she felt about it.

Harley clicked her fingers again, and a figure from the shadows threw her a black top hat with a red ribbon bound around it.

"Yes you do," Harley tutted dismissively, holding the hat out to Harry. "Pull a rabbit out of it for me. Pretty please; I'll be ya best friend."

Harley was grinning at him, bouncing on the soles of her feet. She looked like a child on their first visit to a Muggle magician, and Harry doubted she was going to react negatively to him using magic. The negative side for him, of course, was that he would be breaking Secrecy Laws, but Erkens specifically mentioned that real Aurors knew when to break the law, and if Harry got on the good side of the Joker's partner-in-crime, then it would get Harry better results than mixing with the low-level thugs of Joker's gang.

With a sigh, Harry slipped his wand from his sleeve, fighting back the smile when Harley whooped. She's a criminal, Harry told himself, not some audience member you're trying to enthral.

The theoretical laws of magic wouldn't actually let Harry conjure a rabbit out of thin air, but the closest he could get would be to transfigure the hat into a rabbit. Though Harry had been decent at Transfiguration, it wasn't his best of subjects, and when he cast the spell, he managed to produce a fluffy white rabbit, but with a shrunken top hat stuck on top of its head.

Clapping sounded from the shadows, revealing there were at least three men standing watch, and Harley cheered, grabbing the rabbit off Harry.

"Oh Mr. J is gonna love ya!" she beamed, tossing the rabbit to the side carelessly, and Harry saw hands quickly reach out to grab the animal. Harley leaned in closer to Harry, until her lips were almost pressed against his ear. "Between you and me, Puddin's just not been feeling himself lately. Maybe you can cheer him up."

Harley looked hopefully at Harry, who could only assume that Puddin' was the Joker. Harry could see the devotion in Harley's eyes though, and it softened Harry to see the more human side of the apparently psychotic woman.

"What's happening to my friend?" Harry asked as Harley grabbed hold of his wrist and starting pulling him along.

"Our boy'll be roughing him up about now," Harley answered with a smirk. "And then he'll be taken for auditions. Hey, Robbie?" she yelled to one of the men behind them. "Are we killing our applicants today or letting them through?"

"They're living today," Robbie shouted back. "Killed them twice in a row now."

"Well ain't your friend lucky, then?" Harley laughed, her fingers tightening around Harry's wrist. "You would have never had to audition; you're too pretty for that. We needed a pretty face to brighten up the place."

"What abouts yours, Miss Quinn?" a henchman spoke up nervously, and Harry winced in pain as Harley span around, twisting her fingers over Harry's skin in the process.

"Shut up!" she growled, kneeing the man in the crotch, giggling when he collapsed to the floor in pain. She turned back to the front and gave Harry a wide smile. "Oh just wait and see, Green Eyes; you're gonna love Mr. J!"

X

Sionis Steel Mill was like every other steel mill Harry had seen from the outside – not that that had been many. Despite never going inside one, however, he was sure that the Joker's lair was very different from the usual mills. For one thing the place was very run down, with panels of wood discarded on the unstable stone floor, and flakes of various materials floating down from the walls. There were several additions that looked out of place as well; balloons and flags of green, red, yellow, and blue decorated the rooms, and simplistic clown faces were spray painted onto the walls. Giant tin soldiers stood like guards by the doorways, and brightly coloured fairy lights replaced the usual ones.

The thugs following Harley eventually left them, and Harry followed Harley through the steel mill and towards room which had the words Manager's Office scrawled on the door.

"I'm home, Mr. J!" Harley announced happily, dragging Harry into the room. "I've brought you a magician! His name is Harry."

At first Harry didn't think anybody else was in the room with them, but then a dark laughter echoed off the walls, and a man stepped into the light.

Judging by his white face, green hair, and painted smile, Harry knew this was the Joker. He was clothed in purple pin-stripe trousers with a jacket to match, a mustard yellow shirt with a green bow-tie, and white gloves. But he looked different from the photograph too, like he was ill. The Joker's green hair was thinning slightly on top, and his face; the only bit of skin Harry could see, was littered with sores and welts.

"Harley, you can't bring home every boy who says he's a magician," Joker drawled, his voice changing somewhat in tone with every word he spoke.

Joker moved his hand into his pocket, and with instincts only an Auror could have, Harry had his wand out, freezing the knife Joker had thrown at him in mid-air.

He flicked his wand and sent the knife zooming pass Joker's head, embedding the blade into the wall behind him.

"Told ya," Harley grinned, sticking her tongue out at Joker.

Joker wasn't looking at Harley though; his focus was entirely on Harry, and he looked positively enthralled.

"Well, what do you know? A real magician," Joker mused, making a dramatic effect of flopping into a seat. "Oh I think you and I are going to have some real fun around here."

"So we can keep him?" Harley asked hopefully, and Harry rather resented them talking about him like he was a dog.

"You know I can never deny you, my dear," Joker cooed. Harry was sure Harley almost swooned in delight at Joker's words.

"Yay!" she cheered, running forwards to throw her arms around Joker's neck. The man didn't hug Harley back, and instead simply looked bored, but he kept his eyes locked on Harry's. Harry felt uncomfortable looking into those crazed orbs, but for some reason he just couldn't bring himself to look away.

Harry didn't even manage to look away when Harley dragged him into a hug as well. He felt his heat flush at the close contact to the woman, and Joker winked at him which only served to increase the flush on his cheeks.

"So this magic; can it be used on people?" Joker asked, leaning forwards on his chair and propping his chin on his hands. Harry nodded cautiously, which made Joker's painted smile stretch as he produced an actual grin. "Perfect! I know some doctors who would be more than willing to be sawn in half."

Somehow, Harry knew that Joker meant that quite literally.

"And he's promised to keep you entertained, Puddin'" Harley told Joker, though Harry had said no such thing. "If he doesn't then we're gonna kill his grumpy friend."

Joker cackled madly, and as Harley began to giggle as well, Harry truly did feel like he had been thrown in the madhouse.

He didn't have a choice but to stay and allow himself to be treated like a circus animal. For one thing, Erkens would be killed if he didn't, and secondly, how else would he get a chance to be this close to Joker himself?

The situation was not ideal, but it was the only opportunity he had. He needed to do this for both the Aurors, and the people of Gotham. If the walls of Arkham City ever broke, the mayhem unleashed on the city would be unimaginable.

No, Harry was going to have to endure the craziness, and he could only hope that his own sanity remained in one piece.

X

Harley left Harry and Joker alone after a while, and Harry got so uncomfortable with Joker staring at him that he decided to do some simple spells, both to keep Harry distracted and to get Joker's attention off of him.

He only did simple spells, like opening and shutting the door, and setting the Engorgement Charm on a spider that had been scuttling in the corner of the room. Even with the spells, Harry could feel Joker's eyes on him, and when Joker eventually spoke, Harry was surprised he didn't jump out of his skin.

"So is it you that's magic or the stick?" Joker asked, peering at Harry intently.

"Both," Harry answered, wondering if Joker was planning on killing him and stealing his wand in the hopes of becoming a wizard himself. "My wand wouldn't work if I wasn't magical," he added, making sure Joker got the point.

To prove it even more, Harry set his wand down on the floor, stepped away from it, and Apparated to in front of Joker's chair.

Joker blinked in surprise, and then clapped enthusiastically.

"Bravo! Bravo!" Joker cheered, not quite patronisingly. "How delightful. Have you ever met a fellow named Batman? Quite tall, blue eyes, likes to dress like a giant bat. No? Well one evening with you and I think he'd become crazier than I am."

Harry didn't think that would be possible, even for a man who dressed as a giant bat, but he didn't comment and instead walked back to his wand. As he picked it up, Harley came back into the room with a bundle of red and black fabric in her arms.

"Here you are Green Eyes," she said, thrusting the clothes at Harry. "Can't have you wearing that boring old stuff."

The Aurors had provided Harry with plain black Muggle clothing in an effort to help him blend in, but in a place like the Joker's lair, it only made Harry stick out like a sore thumb.

It took him a moment to realise that Harley was standing in front of the only exit.

"Shut your eyes," he said, feeling more stupid than he had done in a long time. He was used to changing in front of the boys he shared a dormitory with at Hogwarts, but changing as an adult in front of other adults was a different story altogether.

"You haven't got anything we've not seen before," Joker taunted, winking at Harley who licked her lips hungrily.

Harry knew he should have found that disturbing, but for some reason the image sent a pleasant tingle through Harry's skin. Shuddering at his own reaction, Harry quickly shed his coat and pulled his shirt off, holding it to his chest for cover.

He could feel the pair leering at him as he slipped the red t-shirt with black diamonds printed on it over his head. It was his size, but designed to be tight, and he didn't feel much more comfortable with it on than he had been without. Harry blanched as he discovered the trousers were leather, but he reluctantly pulled his current ones off, keeping his eyes fixed firmly on any spot where he couldn't see Joker or Harley, and tugged the black leather onto his legs. The trousers had a red diamond on the side of the thigh to match the symbols on his shirt, and the material fit him like a second skin, which made the boots Harley had provided him with; one black and one red, fit over them perfectly.

Harry would have found the outfit cool had he been wearing it on his own terms and not forced to change into it in front of two other people.

"Oh, much better," Harley beamed. "I'm gonna show Green Eyes the mill, Puddin'."

Joker grunted in response and waved his hand to permit them to leave, and once again Harley grabbed Harry's wrist and dragged him along with her.

While Harley pulled him through the building, they passed a group of thugs, who were encircling Erkens.

They parted to let Harley pass, and Harry realised that though Joker was definitely in charge of Harley, she was far higher in the hierarchy than his everyday henchmen.

The movement of the men revealed Erkens in full. He had been stripped down to his vest and boxers, though Harry could see the man's wand tucked into the waistband of his underwear. A bruise was already forming around one of Erkens' eyes, and his hair was ruffled, but he caught Harry's eye, quickly studied Harry's change of clothes and Harley's grip around his waist, and nodded in approval.

Strange how Erkens was finally pleased with Harry's skill as an Auror when Erkens had it a lot rougher than he did.

Harley pulled Harry along before Erkens could say anything, and ended up leading him to a small room that looked like it was Harley's personal space.

The walls were covered in posters of the Joker's face, most of which had lipstick stains across them, and a harlequin style hat was resting on a hat stand.

There was a window in the room, not looking outside but to another room, and in that room was something Harry had never seen in the Muggle world.

It was a man far larger than any he had seen before, barring perhaps Hagrid who had good reason for being as tall as he was. The man in front of Harry now, however, was not half-giant, but not human either. His bones were sticking out of his skin on his shoulders, back, and face, and his veins bulged vividly out of his hugely muscular arms and chest. His clothing looked like it had been stretched all at once, and was in tatters on his upper thighs and arms. Harry felt a stab of revulsion as he imagined Voldemort craving minions like that.

"What happened to him?" he asked Harley, and he was shocked to see the woman had tears in her eyes.

"Titan," she answered, shaking her head sadly. "It's a chemical that makes people grow like that. Mr. J, he-he took some Titan, but he took too much of it. It's all stupid Batman's fault, and now my poor Puddin' is-"

Harley paused, clutching her hand against her chest as she sobbed, and Harry gently laid a hand on her shoulder, feeling the need to comfort her.

The action brought Harley back to reality, and she turned to Harry with hopeful eyes.

"You're a magician," she stated, and Harry felt a sinking feeling as he realised where Harley was going with this. "You'll heal him for me, won't ya? Please, can you try?"

Harry didn't know the first thing about medicinal magic, but he didn't have the heart to say no. Harley was clearly in love with Joker, and criminal or not, Harry couldn't stand by and let a woman lose the man she loved. It wouldn't hurt to try.

"I'll try my best," he promised, and Harley grabbed in a tight hug.

"Let's not tell Mr. J just yet," Harley whispered into his ear, which once again made Harry flush. "It'll be a nice surprise."

Determined to get on with it, as soon as Harley left him, Harry sat down to write a note. George Weasley had invented a spell and parchment combination, which allowed a witch or wizard to transfigure whatever they had into a piece of parchment, write a message, and then cast a spell with the recipient's name tagged at the end. The invention had been a revelation in the Wizarding World, and the Weasleys no longer had to live in poverty. It had also been taken on board by the Aurors, but Harry needed Hermione now.

Hermione, he wrote, pausing as he considered how to word it.

Our mission itself is going smoothly so far, but my partner has ingested and become poisoned with an unknown chemical. Are you aware of any spells or potions that can cure any poisoning? I don't think I'll be able to get my hands on a Bezoar. Maybe you could ask Luna if she knows any herbal remedies. Give my love to the family,

Harry

He cast the spell and watched the piece of parchment crumble into thin air.

Harry just hoped Harley didn't expect a miracle off him any time soon.

X

Harry watched with feigned interest as the Joker's skin cleared, all traces of the scars and scabs disappearing.

Of course, they had only been hidden temporarily by a Concealment Charm, but as far as Joker knew, Harry had sorted out his skin problems. If the charm fell, Harry would have to lie and say it was the illness fighting back, but he felt comfortable with the situation.

For somebody who was apparently nothing more than a psychotic serial killer, Joker certainly cared about his appearance; although perhaps it was more about surviving. Nothing was ever said outright – Harry had learnt that in the two days he had been in the Joker's hideout – but Harry got the picture.

And because he needed to stay on Joker and Harley's good side, he had pretended to completely cure the skin related symptoms of Joker's illness. He had heard of doctors failing to cure Joker and being brutally killed, and he didn't hope to meet that end; Harry was more than aware that the novelty of his magic could wear off at any moment if he wasn't careful.

"Oh, I look marvellous!" Joker exclaimed cheerful, examining himself in a handheld mirror. Harry winced when Joker prodded at his magically disguised face, but Joker just seemed to grin widely in satisfaction. "It's so silly being so obsessed over one's appearance, but I just feel I have something to prove."

Joker trailed off, his usual joyful disposition fading away, and he cast his gaze downwards. The change was unexpected, and Harry couldn't help but be curious as to why.

"Like what?" Harry asked, not sure if he should expect an answer or not.

But then Joker looked at him with an intense gaze, the wild green orbs sparkling with something Harry couldn't understand.

"My father always said I was a disappointment," Joker said in a hushed tone, glancing around as if he was afraid of being overheard. "Said I was an ugly freak. No, my father wasn't a very nice man, but I just loved him, like a boy was supposed to love his father. He died in a freak accident years ago, but I've always wanted to make him proud of me. Silly, isn't it?"

Joker giggled, despite his serious tone, and Harry wasn't sure what to do apart from blink.

Harry was instantly reminded of Voldemort, and it wouldn't surprise Harry if freak accident was another phrase for murder, but the sudden change in Joker's character and facial expression made Harry believe there was some truth in what Joker had said, if not the whole truth.

"I was called an ugly freak growing up, too," Harry admitted quietly, wondering if opening up about himself might make Joker do the same back. "My aunt and uncle were scared of my magic, and they were certainly never proud of me. They just acted so-"

"Ashamed?" Joker supplied, leaning forwards and fixing Harry with a dark smirk. Harry couldn't help but shiver.

Harry nodded, and Joker smiled, the painted grin stretching wide across his face.

Somehow, the fact he could relate to well to yet another psycho didn't make Harry feel as uncomfortable as it should have done.

X

"You know, I don't think Batman understands why I do what I do," Joker mused aloud one day, speaking for the first time in an hour.

He had been watching Harry set a number of things on fire and then extinguishing them with a variety of spells. Harry had been requested to perform magic for Joker and Harley a lot, rather like he was a court jester of sorts.

Harry didn't mind though. Harley positively adored him and his magic, while Joker seemed interested enough that Harry felt confident the man wasn't planning on killing him anytime soon. Erkens was a different story, because Harry had only seen him twice since they had found themselves in Joker's lair. On both those occasions, Erkens had signalled for Harry to continue as they were doing, and Harry supposed that even though they were in a precarious situation, he was at least getting some information out of Joker and Harley.

Harry had discovered that there were numerous gangs in Arkham City, and Joker's main rival was a man who called himself Penguin, though it seemed that most attacks Joker made on Penguin's men were simply to kill them rather to take over his territory. Although Joker was taking over territories all over Arkham City and fast; delaying his attack on Penguin was a form of psychological torment.

Harry also learnt that Joker had some sort of alliance with a man named Hugo Strange, and Harry vaguely recognised the name belonging to one of the masterminds behind Arkham City. From what Harry could make out of Joker's comments, Strange was planning something terrible which would kill countless people. Joker hadn't gone into detail when Harry had asked though. "Don't worry your pretty little head," Joker had told him. "You won't be burning at the stake any time soon. But maybe I'll roast one of those idiots Batman knocked out; I'm in the mood for marshmallows."

Joker also had a very deep obsession with Batman, which seemed loving as much as it was hateful.

"Why doesn't Batman understand you?" Harry asked, realising Joker had wanted him to do so, as though he was building Joker up for the punch line of a joke.

"Because he doesn't know what it's like to have been forced to grow up so fast," Joker declared, clutching his hands over his heart theatrically. "My parents died when I was eight, you see; mugged and shot before my very eyes. Oh, I had a butler to keep me company, but I never got to be a child again. I suppose that's why I kill and slaughter; it gives me a childlike happiness."

A nerve struck inside Harry, with Joker's words echoing his own experience. Being orphaned and growing up without a proper childhood wasn't easy; look how Tom Riddle had turned out. Harry would always be grateful to the people who saved him turning out like that; Hagrid, the Weasleys, Hermione, Sirius…all of them and more had shaped him into a good person.

Although hadn't Joker said his father died in a freak accident? Maybe Harry had judged him too early when he thought that was another way of admitting to have murdered him. Perhaps to Joker, being mugged and shot was a freak accident.

"I was orphaned too," Harry said, offering Joker a sympathetic smile. "My Aunt and Uncle didn't love me, and so I was neglected and treated like vermin. My bedroom growing up was the cupboard under the stairs; that's how bad they were. So I guess I can relate to you, in a way, because I missed out on a happy childhood while I had to watch my cousin grow up spoilt and loved."

"But you're so good!" Joker exclaimed, leaning into Harry until wild green eyes were inches away from his own. "You don't stab people or throw them into meat grinders; that's an ordinary Tuesday for me."

No, Harry wasn't a brutal killer, but he could have turned out much worse than he had done. If magic hadn't existed, and Harry never escaped to Hogwarts, he would have ended up going to the local public school with his tatty grey rags as a uniform. He would have no doubt been bullied because of his looks and left friendless, and forced to suffer through five years of school until he was old enough to leave at sixteen with minimal qualifications. The Dursleys would have kicked him out as soon as they could, and he would probably only have been able to get a poor paying job, which would have left him living in the rough areas of town, where drugs and prostitution were rife. He might have ended up an addict or in a street gang, left bitter and hateful of the world.

"I don't blame you," Harry told Joker, patting his hand, and he meant the words. "The world made you like this."

X

Harry stepped back quickly, dragging the door to slam it shut behind him.

He blinked once, then twice, and then shook his head, trying to shake the vivid image out of his mind. Though the stirring in his lower body made him question whether he actually wanted to forget.

One of the goons had told Harry he was wanted in the Manager's Office, but when Harry arrived, Joker and Harley were in the middle of fucking each other.

And Harry just couldn't understand why he found it so damn arousing.

Harley had been on all fours, and Joker had been thrusting lazily into her from behind, sock puppet on his hand.

The sock puppet was easy to forget, thankfully, but even now he could see Joker and Harley clearly in his head. They had been facing the door as well, looking at him with identical grins, and Harry wondered if it had been planned, but then again, why would they have wanted Harry to see?

But no matter why or how it had happened, Harry was hard because of it. And to make matters worse, he didn't think it was purely because of Harley either.

Harry didn't have anything against homosexuality, but he had never found himself sexually attracted to other men. So why was it he couldn't picture Harley on her own? And why was it no other man, but Joker specifically? Merlin, Joker's firm thighs pushing against Harley's body hard; her breasts bouncing as Joker moved against her…fuck!

Perhaps the fumes of the steel mill had somehow got to his head. Yes, that had to be it.

His cock twitched mockingly, and Harry growled. First to sort out his body; his head could wait.

X

"So did you like what ya saw earlier?" Harley questioned, jumping on Harry from behind and looping her arms around his chest.

He immediately felt his cheeks redden, and his awkwardness was made ten times worse by the feeling of Harley's soft body pressing against his.

"Sorry about that," Harry mumbled, pulling out of Harley's grip. "Oh, I've found a cure for Joker."

Harry's plan to change the subject had worked, and Harley seemed to have forgotten her teasing as her face filled with excitement.

Hermione had finally replied to him, with the instructions on how to make a Cleansing Potion. Apparently it cleared a person's body of any toxins, and was made from natural ingredients that shouldn't be too hard to find. The instructions for brewing the potion didn't seem too difficult either, although Harry wasn't the greatest in that area, but he supposed he could ask Harley if he could borrow Erkens to help if he ran into any difficulty.

But first he had to get the ingredients, and Harry had no idea where he'd find so many plants in an industrial city when it was middle of winter and freezing cold.

"I've got instructions for a potion that will clear the toxins, but I'll need some help," Harry informed Harley, passing her the list of ingredients. He had torn it off from the rest of Hermione's letter, which had been a message of love and concern. "I don't know where I can find any of these ingredients."

"I can get ya this stuff, no problem!" Harley beamed, waving the parchment around cheerfully. "This plant lady named Ivy is my friend; she'll get me all we need."

And then Harley pushed up on her toes and kissed Harry firmly, before pulling away with a "mwah!"

"See ya later," she grinned, winking at Harry before strutting out of the room.

Harry stared open-mouthed as she left. It had been a quick peck, nothing more, but Harry's heart was racing, and he could still feel the stickiness of her lipstick on his mouth.

Despite having frozen at the time, Harry had still enjoyed the kiss, but weren't Harley and Joker together? Harry wasn't sure how possessive Joker was over Harley, but he decided he wasn't quite ready to find out.

X

"And he dresses so darkly!" Joker complained, making sure Harry was listening to his rant about Batman by slapping his arm every so often. "Would it kill him to add a little bit of colour once in a while? Hell, he could kill someone else and spruce up his tights with a splash of red."

"Black and red is Harley's thing, though," Harry mused, all too aware that his own clothing was the same colours, marking him as Harley's.

"Speaking of Harley," Joker sang, leering at Harry. "She told me she kissed you, and I can't stand for that."

Shit, this was it. Joker has finally had enough of Harry and was going to kill him.

His hand had just reached his wand when Joker grabbed hold of his shirt and tugged, smashing his lips against Harry's. His wand clattered to the floor in shock, and he froze as Joker ravished his mouth.

Where Harley had been sweet and quick, Joker's kiss was demanding and dominating, with sharp teeth biting at his lips. Harry had never kissed a man before, but it was wonderful, and his cock was growing hard in response.

It took Harry a moment to notice that Joker had stopped kissing him and had settled back into his seat, fixing Harry with a taunting smirk.

"Now we're even," he grinned. "Now where was I? Ah, yes, the tights. I like to think I'm pretty flamboyant, but why did Batman decide tights would be a good idea? They could get a ladder in them so easily…"

Harry drowned out the rest of Joker's words, surprised he could even hear them over how loud his heart was beating. He was just so confused.

He had recognised that he was attracted to Harley, and definitely felt affection for her, whereas Joker was different. As much as he loathed to admit it, Harry had fallen for Joker too, and seemed to have developed this sexual attraction out of nowhere. He had always considered himself straight, but he couldn't even find a problem with finding Joker attractive apart from the fact it was the first time he had looked at another man like that.

They were separate people as well, a couple, but separate people nonetheless, and Harry liked both of them, and both of them seemed to like him. Weren't relationships meant to be between two people? But why did they have to be? Harry couldn't think of anything wrong with being in a relationship with more than one person; it was society that said to limit it.

The worst thing of all was that Harley and Joker were both violent criminals. They both freely admitted to enjoying mindless killing, yet Harry had fallen for them anyway. Or had he fallen for the people behind the killer? Joker especially had had a difficult upbringing, so closely echoing Harry's own.

And hadn't Dumbledore always said he thought Tom Riddle could have been saved by love? If Harry loved Harley and Joker enough, perhaps in time they could both change.

Harry was jolted out of his thoughts when a received a sharp slap on his wrist.

"Pay attention!" Joker growled. "I don't know; kids today."

X

"I've poisoned Batman with my blood," Joker announced cheerfully one afternoon.

Harry stared, watching as Harley nodded excitedly behind Joker, looking much like a playful puppy.

"Why?" Harry queried; he had rather been under the impression that despite their animosity towards one another, Joker actually enjoyed Batman's company. In an odd way, of course, but killing Batman would take a lot of fun out of Joker's life.

"I just don't think a man who dresses up as a bat would be good at time management, otherwise," Joker tutted thoughtfully. "If he dies so does everyone else! Of course, Harley'll steal the cure off him when he makes it, and the lovely citizens of Gotham will perish anyway, but don't tell him; you'll ruin the surprise."

Harry was somewhat lost; why would Gotham residents die as well? Unless Joker had somehow poisoned the blood supplies in the city hospitals, but he didn't bother to ask for clarification; if Joker was going to tell him then he would know by now.

"Oo, but guess what, Mr. J," Harley grinned, bouncing on the balls of her feet. "Green Eyes is making you a magic cure as well."

Well that answered Harry's other question about whether Harry's job had fallen to Batman now.

"A magic cure, eh?" Joker sang, leering at Harry. "For someone as boring and un-magical as little old me?"

Harry nodded. "Yeah, err, Harley's helping me with it."

"Ah, well aren't you two just wonderful? What would I do without you?" Joker beamed, and Harry felt a strange stab of pride inside him. "Well, get on with it then; I have a phone call to make, and I would like a little privacy."

X

Getting the ingredients for the Cleansing Potion had been easier than expected thanks to Harley's help, but actually make it was more difficult than Harry had anticipated.

It wasn't that it was a complicated potion, but more that it was rather fiddly, and Harry always had been hopeless at that.

He had asked Harley if Erkens could help, and she had agreed and collected the older man for Harry.

Erkens looked somewhat dazed and was sporting a number of bruises and cuts on every inch of skin that Harry could see. His face had been painted in white make up, with bright red lips and black diamonds over his eyes, giving him the look of a circus clown.

"How's it going?" Erkens asked once Harley left the room, managing to sound serious despite his look.

"Fine," Harry answered with a shrug. "Are you alright?"

"A bit rough, but I can handle it," Erkens said, automatically slicing the leaves Harry passed to him and tossing them in the pot Harley had found, propped above a Bunsen burner. "Joker's guys are perfect for him because they're violent brutes but a bit dim-witted, which makes them easy to control. I've found out quite a lot about these gang wars and how all these prisoners have got their hands on weapons. What about you? Find anything from Joker himself?"

"Some stuff," Harry nodded. "He's a bit vague at times, but I've passed on everything to the Aurors." That last bit was a lie; Harry had sent a couple of messages to the Auror department, but he kept on forgetting to send them the information. Part of him didn't want to at all, but he knew there was a reason he was here.

"What's this potion for anyway?" Erkens enquired, dicing the next ingredient at Harry's request. The ingredients were almost all done now, and then all there was to do was simmer the potion for an hour while stirring it clockwise every ten minutes.

"Joker wanted me to make one, that's all," Harry mumbled, hoping Erkens didn't get too interested in the reason. The man wasn't an Auror for nothing, though.

"Why? What good does making a potion do for him?" Erkens carried on, dropping his scalpel as a look of realisation crossed over his features. "You're not-? Are you trying to cure him?"

"Of course not," Harry said quickly, moving to stand between Erkens and the pot in case the man tried to knock it over. "But even if I was, why does it matter? Do you really want him to die without telling us everything?"

"He's a monster," Erkens growled, leaning over Harry, and with his massive height, Harry had no shame admitting he was intimidated. "He deserves to die. His girlfriend will probably off herself afterwards, and then those thugs won't know what to do with themselves. His whole crew will fall apart, which means one less gang for us to deal with."

"He does not deserve to die," Harry hissed, the urge to defend Joker stronger than his desire to play nice with Erkens. "Get out; I don't need your help anymore."

Erkens raised his fist as though he was going to punch him, but then he backed off, and gave Harry a strangely pitying look.

"I knew they shouldn't have sent you," he muttered, angrily finishing his dicing before throwing the scalpel on the floor. "I guess we can add you to the list of Joker's victims now."

And then Erkens stormed out of the room, leaving Harry fuming.

How could he call Harry a victim? All because he didn't want somebody to die. Aurors had to be tough, but they didn't have to be heartless.

"What's the matter with that bozo?" Harley asked as she came through the door Erkens left just moments ago.

"He said Joker deserved to die," Harry muttered angrily, watching the potion bubbling gently.

"What a jerk," Harley agreed. "Well don't ya worry, Green Eyes; he won't get away with it!"

X

Harry jumped when an explosion sounded in the distant, and the ground began to shake beneath his feet.

"It's time!" Harley said excitedly. "Is the potion ready? Good, we gotta take to Mr. J in the tunnels."

Harry stirred the potion one last time before removing it from the Bunsen burner and following Harley through the mill and into an underground tunnel.

"What's happening?" Harry asked as another explosion shook the world around them. Thankfully being underground meant only the vibrations were getting to them, but Harry didn't envy anyone who was above ground, even if he didn't know what was going on yet.

"I dunno, really," Harley answered with a shrug. "I heard Strange was gonna kill us all or something, so we built these tunnels to keep us safe."

Harry remembered Joker mentioning something about everyone dying before; he could only presume they were bombing the prison. Part of him wished that he could go and help, but he knew it would be impossible, even with magic.

Harley led Harry to a small room where Joker was already holed up. The man was coughing violently, and Harry hoped desperately that the potion worked.

Harley snatched the pot from Harry's hands and ran over to Joker, who grabbed it from her just as roughly. Joker downed the contents and then looked down at his body expectantly.

Harry subtly cast Finite to drop the Concealment Charm, and grinned triumphantly when he saw the red marks fade into Joker's skin. The green hair started to grow thicker and more vibrant in colour, and everything about him just started to become brighter.

"How do ya feel, sweetie?" Harley asked, watching Joker nervously.

"Wonderful," Joker hummed, banging on his chest. "Quite dandy, actually. Better tell Clayface there's been a change in plans."

Harley squealed, and drew Joker into a kiss.

Harry dropped his gaze to the floor, suddenly feeling awkward, but then Harley was in front of him, kissing him instead.

She was almost immediately dragged backwards, and Joker had taken her place, kissing Harry deeply.

Joker pushed Harry until he fell into a chair, and Joker's fingers pressed down on Harry's wrists to keep him still.

Harry looked up nervously, feeling too breathless to speak, when Joker pulled a tube of lipstick out of his pocket and ran it over Harry's lips. Harry squirmed, but Joker added pressure with his fingers, forcing Harry to keep still to stop the pain.

When Joker finished he tossed the tube across the room, and Harry darted his tongue out to dab at the heavy coating on his lips.

His attention fell back to Joker when he felt a hand playing with the zipper of his trousers.

"What are you-?" Harry started, his words trailing into a whimper when Joker's gloved hand closed around his hardening cock.

"Just a bit of fun," Joker grinned, licking his lips. "What else do you get a pretty magic boy as a thank you gift? Oh, apart from this."

Joker snapped his fingers with his free hands, and Harry's eyes widened when Harley dragged a body into the room.

"Told ya he'd be sorry," Harley laughed, kicking Erken's corpse in the side.

"You killed him?" Harry breathed, shutting his eyes as Joker toyed with his erection, stopping him from going soft.

"He deserved it," Harley shrugged. "Don't worry, Green Eyes, we'll make ya forget."

Joker moved back from Harry to seat on an armchair, watching with a lustful gaze as Harley sank to her knees in front of Harry and took his member in her mouth.

Harry cried out, keeping his eyes firmly shut as Harley sucked him. Her hands were on his wrists, asserting her dominance over him, but her mouth was so wet and warm and good that he didn't care about her fingers digging into him.

One of her hands released his wrist and tugged his trousers down, and Harry jerked when a finger pressed against his arse.

"What-?" he began, snapping his eyes open, but he found himself unable to speak when Harley pressed her saliva slickened finger inside of him. He had never experimented with anything beyond the typical heterosexual sex habits, but Harley's finger wasn't entirely unpleasant. It was more strange than anything, but when she added a second, it hurt more, stretching his body in a way it had been more before.

Harley's mouth continued to work Harry, acting as a bit of a distraction from the fingers inside of him.

"Come on, Harley," Joker hissed; Harry had almost forgotten he was there.

Harley pulled her fingers out of Harry and got to her feet, pulling Harry with her. She dragged Harry to where Joker was sat, and pushed him on his lap.

Harry felt a stab of panic hit him when he felt Joker's erection rubbing against his arse. Surely Joker wasn't going to…?

"I'm not gay," he said quickly, even though he knew that didn't matter. He had had fantasies involving Joker's cock; not necessarily inside of him, but that was because he didn't know how it would work without a lot of pain.

"Does it matter?" Joker laughed, spitting on his hand and spreading it on himself. And then he shifted so that his cock was against Harry's hole, pushing up inside him.

"Fuck!" Harry hissed as his entrance stretched around the intrusion, burning and sore. Harley's preparation had definitely not been enough, and it was too dry, but Joker didn't seem to have a care in the world as he continued pushing upwards.

And Merlin, it hurt. Nothing like the Cruciatus, of course, but that was easy to forget when you had a cock up your arse.

Harley kissed Harry again, as if she sensed his pain. She squeezed his cheeks, forcing him to open his mouth, and she thrust her tongue inside, demanding and possessive as Joker had been.

And then Joker's cock hit something inside of Harry that somehow made all the pain worth it.

Harley grinned into the kiss, shifting herself onto Harry's lap, settling over his erection.

Harry couldn't help but groan as Harley sank onto his cock, and the dual sensations of Harley's tight warmth and Joker's cock pressing against that spot inside of Harry made him remember exactly why he had fantasised about this.

Joker was thrusting lazily upwards into Harry, and Harley rocked her hips, bouncing on Harry's lap, and even though it still hurt like crazy, the pleasure sensations made the pain more bearable.

Harley pressed her thumb against Harry's lower lip, smearing the lipstick across his mouth. She kept her thumb there, leaning forwards to press her breasts against Harry's chest, and he allowed his hands to move up and grab them.

Harley moved wildly in response, which made Joker's cock rub even more insistently against Harry's prostate, and Harry didn't know how he had lived without these people in his life.

"Did you know?" Joker murmured, "that karaoke is Japanese for empty orchestra? My, how hauntingly beautiful."

Was Joker reading a book?

Harry twisted his head to see that yes, Joker was reading a fact book, but then he noticed Harry looking and thrust up especially hard.

Harry could feel the pressure in his cock building up, and when Harley reached her climax it made her clamp tightly around Harry's cock, and he couldn't hold it anymore, releasing inside of Harley.

Joker didn't take much longer, and he spilled inside of Harry, while simultaneously expressing his amusement that the word hippophobia meant a fear of horses.

"See, that was fun, wasn't it?" Harley smiled, sliding off Harry. "Maybe next time I can do ya? I have a toy Mr. J won't let me use on him."

X

Although the first time having sex with Joker and Harley had been interesting, it had definitely awakened a side in Harry he didn't know he had. The second time Joker fucked him hadn't been nearly as painful as the first time, and it only got better as time went on.

Joker wasn't heavily into sex, and usually had something else going on at the same time. Harley showed Harry a scarf Joker had knitted once while they had been fucking.

That didn't mean Joker was any less in charge though, and even if he wasn't doing anything, he was still the most dominant person in the room.

Submission wasn't something Harry had really considered before, but it just seemed natural with Harley and Joker. It wasn't in a Dom and Sub way, but more in the general atmosphere and behaviour of them all.

Harley was rather insatiable, and in only two days she had exhausted Harry. But he had learnt new things about himself, and discovered experimenting was rather enjoyable.

Harley was currently persuading him to help her to convince Joker to get her friend Ivy involved for an evening, but then Joker distracted them by strolling across the room.

"I'll be back soon, dearies," Joker sang cheerfully. "I'm just going to go and become immortal."

"Okay, sweetie, have fun," Harley said, waving as Joker strolled past them.

"Did he just say he was going to become immortal?" Harry asked Harley, not entirely sure if Joker actually meant it or if it was just a joke.

"Yep," Harley nodded, and Harry felt his heart sink. "Said something earlier about a Lazarus Pit. Don't really know what that is, but-"

"Harley, we have to stop him," Harry interrupted, his heart pounding heavily in his chest. "Trust me; quests for immortality do not end well, no matter how good it seems at first. I knew a man who tried to become immortal, and it messed him up physically and mentally. He basically looked like a human snake; he had slits for a nose-"

"Mr. J would strange without a nose," Harley cut in. "His mouth would be too out of proportion. How are we gonna stop him?"

"Do you know how to track him?" he asked, and Harley nodded. She jumped to her feet, gesturing for Harry to follow her.

They travelled through the underground tunnels, and when they eventually came out onto the main part of the prison, Harry couldn't help but gasp. Protocol 10 had certainly done some major damage.

Buildings had crumbled and roads were smashed, while the snow that was still falling covered everything in a light grey coating which only served to make the place look even bleaker. A number of bodies were slumped on the ground, some of them dressed in the grey uniforms that signified the political prisoners who had done nothing wrong apart from pissing off the wrong person.

Harley didn't seem to give anything a second thought, and carried on her path. It seemed that she knew every part of Arkham City, and had incredible agility skills. Harry was only able to keep up because of his Auror training.

They ended up at a theatre, running in just as a massive explosion shook the building.

Harry instinctively pressed Harley against the wall, checking the area for any signs of danger. Everything seemed stable though, and after a moment Harry let Harley free.

Doors to another room banged open, and a man dressed entirely in black armour, complete with a cape and masked helmet strode through, and Harry didn't need to see the bat symbol engraved on the chest to know that the man was Batman. Harry had thought Joker had been exaggerating when he described Batman, but apparently not.

Batman didn't look twice at them as he walked, and, without turning around, he swung his arm out suddenly, smashing Joker in the face, who had tried to jump at him with a knife.

Before Harry knew what he was doing, his wand was in his hand, and he muttered "Stupefy!" The red beam struck the costumed vigilante, and he collapsed to the floor unconscious.

"That was handy," Joker drawled, looking from Harry to the prone form of Batman. "Fancy taking him back to base? I just know Batsy would love to meet you."

"Sure, I have some spells I bet you'll both love," Harry grinned.

His pocket felt heavier all of a sudden, and Harry pulled out the piece of parchment that he had been sent.

'How is it going? Did the potion work? Love, Hermione.'

Harry screwed it up and tossed it on the floor.

What was the point of bothering with his old friends and life? Harry had found somewhere new to belong now.

X

I hope you enjoyed reading this as much as I enjoyed writing it.

Just a note – as much as I love Harry, I don't think he would ever stand a chance against Joker. Harry's weak point has always been his lack of control over his emotions and mind, and Joker is a very powerful mind manipulator.

I'm just saying in case it seems like Harry gave in too easily. This story is from his POV, but I hope I made it pretty clear for anyone who knows the Joker's character that he was saying exactly what he needed to get Harry on his side. Harry didn't know that, though, and another weakness of his is that he likes to see the good in people, just like Dumbledore. Harry could beat Joker physically, but that wasn't how Joker was playing.