Some of the dialogue in the following chapter is from Harry Potter and the Order of the Phoenix (pg 515-517). All credit goes to J K Rowling.
After his initial lessons with Snape, Harry Potter was not anxious for another session of his most hated teacher rummaging around inside his memories. However, he had received his copy of his interview in The Quibbler that morning and was feeling most satisfied as the news quickly spread around the school. Now, he wanted nothing more than to return to the Gryffindor common room, where Fred and George had promised to celebrate the occasion.
Instead, he was kneeling on the floor of Snape's office, sweat dripping down his back.
"Get up, Potter! It's clear you haven't been practising; do you honestly want the Dark Lord to break into your mind?" The greasy haired man sneered at him, indifferent to his suffering and Harry felt rage inside of him at the unjustness of the whole situation.
A knock came at the door and Harry used the time before they entered on sitting back on his chair.
"Professor Snape! Professor Umbridge needs your help urgently!" A tiny Slytherin girl appeared in the doorway, her hair disheveled and winded. "Someone has installed massive posters of The Quibbler on her office door and none of the other teachers seem to be able to remove it!"
The Potion Master's sneer turned into a scowl at this information. "Thank you for informing me, Miss Shafiq." He turned to Harry and his scowl deepened. "Remain here, Potter. We will resume your lesson shortly." And with that, he swept out of his office, the tiny first year scurrying after him.
Not wanting to give Snape another reason to punish him, Harry stayed seated and tried not to fidget. Naturally, he did not succeed.
It was only about a minute since Snape had left the room, but already curiosity had its hold on Harry. He moved towards the pensive and the swirling memories inside it. What was it that Snape wanted to hide from him so badly? Gently prodding the silver liquid with his wand, Harry looked onto the surface and-
"Do you really want Professor Snape to hate you more than he already does?"
Harry twisted around in shock at being caught. Standing in the doorway was another Slytherin girl, much taller than the housemate who had taken Snape away from his office.
"Snape's not here." He replied immediately, saying the first thing that popped into his head.
A sly grin blinked crossed the Slytherin's face. "Of course not, I arranged for him to be elsewhere."
Harry narrowed his eyes at her, not wanting to trust her word for it. "Oh, and how did you do that?"
"I suggested to Lee Jordan that the High Inquisitor would probably appreciate her own copy of The Quibbler and word got to the Weasley twins." She stated this simply, walking away from the door of the office as she spoke. "Then, I made sure that Shafiq got into her good books, as Professor Snape probably wouldn't trust me if I was delivering the message. I also knew that the other teachers hate her and would co-operate as little as possible when removing the posters."
The Slytherin girl was now only a couple of paces away from Harry and he felt a sense of unease fill him. Why would someone go to such lengths to get him alone? The only other people Harry knew with such complicated plans were Dumbledore and Voldemort, so he was quickly on guard, his hand reaching for his wand.
"Why did you do that?" Harry demanded, his wand now safely wrapped inside his palm.
She folded her arms and cocked her head to one side, as if puzzling over something. "Curiosity."
"Curiosity?" Harry was unable to keep the disbelief out of his voice.
The girl shrugged, not seeming self-conscious at all. "My name is Elowen Robins. I also take remedial Potions."
Harry frowned in confusion. Was she saying what he thought she was? "Nice to meet you, Elowen. I'm Harry Potter."
A small smirk formed on her lips. Of course she knew who he was!
"Ellie." She told him, holding out her hand. Harry stared at it uncomprehendingly. The Slytherin sighed. "Call me Ellie, not Elowen."
"Then why did you introduce yourself using a name you hate?" Harry wondered if this was another case of girls being weird. After the Valentine's Day issue with Cho, he was considering whether he should just avoid the other sex altogether.
Ellie beamed at him. "That was before I realised you were a decent person, Harry." Her brow crinkled for a second. "We'd better sit down, Professor Snape should be back soon."
Harry sat back down, while Ellie took the seat next to him. "Why are you really here?" He asked suddenly, uncertain around the younger girl.
"Well," Ellie fixed him with a calculating stare. "Everyone knows that there is a secret society of students that are conspiring against the 'Ministry Approved' decisions made at Hogwarts. It doesn't take a genius to figure out that you're at the centre of it."
And Harry would have replied, only the office door swung open abruptly, revealing a seething Potions Master.
Harry sat back in the Gryffindor common room feeling confused. As soon as Snape had returned to his office, he had barked at Harry to leave and fixed Ellie with such a horrid glare that Harry was surprised she hadn't dropped dead where she stood. Needless to say, Harry left as soon as he could, not wanting to spend any more time with the temperamental Potions Master than he had to.
The twins had produced several more giant posters from The Quibbler and hung it across one of the walls of the common room. Gryffindors surrounded him, all asking him to relive his interview blow by blow, not giving him a chance to consider the oddity that was Elowen Robins. Excusing himself, Harry made his way to his thankfully empty dormitory.
Strangely enough, Ellie reminded him of Luna a little - both were unpredictable, disliked Umbridge (but then, who didn't?) and seemed to think there was some sort of conspiracy going on. Shaking his head of those thoughts, Harry reminded himself that Elowen was a Slytherin and her parents were probably Death Eaters who wanted her to spy on him.
Rubbing his aching scar, Harry climbed into his bed, feeling slightly sick. Closing his eyes, he promptly fell asleep and anger began to wash over him...
Kneeling before him, a man dressed in black robes trembled on the floor. "Master, I crave your pardon." The man's voice was dry and cracked, his head bowed in submission before Harry.
Only now did Harry speak and to his horror it was high and cold, his words laced with cruelty. "I do not blame you, Rookwood."
Helpless to stop himself, Harry prowled closer to the servant until he towered over him. On the floor, Rookwood barely suppressed a whimper. "You are sure of your facts, Rookwood?"
This time, the cold tones didn't affect him as much, but Harry still felt his own terror rise up in perfect symphony to Rookwood's Master's calculating fury.
"Yes, My Lord, yes... I used to work in the Department after - after all..."
Rookwood's voice trailed away before Harry's impatient glare. He rapidly looked down again, avoiding Harry's gaze. "Avery told me Bode would be able to remove it."
"Bode could never have taken it Master... Bode would have known he could not... undoubtedly, that is why he fought so hard against Malfoy's Imperious Curse..."
During Rookwood's explanation, his anger rose into a mighty crescendo until it escaped in a dangerous whisper. "Stand up, Rookwood."
Stumbling hastily, Rookwood complied as quickly as he could, revealing a scarred and fearful face. "You have done well to tell me this," Harry looked down contemptuously at his follower, who stood stooped, frozen mid-bow. "Very well... I have wasted months on fruitless schemes, it seems... but no matter... we begin again, from now. You have Lord Voldemort's gratitude, Rookwood..."
"My Lord..." Rookwood's parched and croaking voice flooded with relief, "yes, My Lord."
"I shall need your help. I shall need all the information you can give me." Harry's words were measured, dangerous but no longer lethal.
"Of course, My Lord, of course... anything..."
"Very well... you may go. Send Avery to me."
Harry turned away in dismissal, as Rookwood scurried towards the door, bowing as he went. On the wall, an aged and cracked mirror hung, illuminated only by the candles in the dark room. His reflection was far from perfect, yet it grew clearer and larger as Harry moved towards it, until he was staring into a pair of red eyes embedded in a pale skull-like face.
And although Harry knew on some level that he was trapped inside the mind of his sworn enemy, despite the fact that he had struggled against his restraints when he heard that iconic voice, he was unable to bear the reflection staring back at him.
"NOOOOOOOOO!"
"What?" yelled Ron's irritated voice.
Flailing madly, Harry wrestled against his bedcovers, succeeding only in tangling himself in further knots, as he fell from his bed. "Would you stop acting like a maniac so I can get you out of here!" Ron swept the hangings to one side and helped Harry to his feet.
"Has someone been attacked again?" Ron hissed urgently, giving a good impression of Nagini. "Is it Dad? Is it that snake?"
"No - everyone's fine -" Harry gasped breathlessly, his scar burning. His mind reeling from the fact that he had been inside Voldemort's head! Images swam before his vision, the long white fingers, Rookwood's pockmarked face and as always the door at the end of the corridor. Turning to Ron's worried face, Harry tried to reassure him.
"No one's been attacked, it was just Voldemort speaking with one of the escaped Death Eaters." He tried to pass it off as nothing, but Ron did not looked reassured.
Taking a sip of water, before he spoke, Ron's voice was rather faint. "You just saw You-Know-Who? Harry you've got to tell-"
Both jumped at the sound of Dean and Seamus entering their dorm, making a great deal of noise as they did so. Harry quickly rearranged himself in a way that didn't make him seem like a nut-job, not wanting Seamus to witness anything out of the norm.
"Look, I'm working on it okay? That's what my occlumency lessons are for." He said quietly.
Ron frowned, his worry still evident. "But it's not like Snape is doing much good is he? The greasy git probably wants you to get your mind invaded!"
"I said that I was working on it, alright?" Harry snapped, because he was. Only his hopes rested on an young Slytherin student, rather than a dark haired dungeon bat.
After telling Hermione about his dream the following morning, Harry was even more resolute to learn occlumency. With both Bode and Sturgis Podmore getting put under the imperious curse to reclaim the weapon from the Department of Mysteries, Harry's dream-obsession with the corridor seemed to make a disturbing amount more sense.
Unfortunately, his newfound resolve was quickly tested, as he was unable to find any trace of Ellie Robins around the school. Every time he used the Marauders' Map to locate her, by the time he got to her position, she was nowhere to be found. Eventually, out of exasperation, Harry decided to just grab his invisibility cloak and wait outside of the Slytherin Common Room until she returned.
Hours later, just before curfew, a tall brown-haired girl walked morosely towards what was commonly referred to as the 'Snake Pit'. Reaching the entrance wall, Elowen was just about to speak the password when a voice came from behind her.
"Ellie!" The girl turned towards the now visible Harry, who had stowed his cloak into his robe pocket.
The Slytherin smiled. "There you are! To be honest, I thought that you had given up trailing me all over the school. Was I really that easy to keep track of?"
"You were avoiding me?" Actually, now that Harry thought about it, that made a lot of sense. "Wait, you knew that I was looking for you and didn't say anything?"
Elowen looked at him critically. "What do you think the rest of my House would do if they caught me speaking to you in public? The upper years have parents who were Death Eaters and the entirety of Wizarding Britain thinks that you are a dangerous attention-seeking individual of dubious mental stability. You also are the very embodiment of Gryffindor-Slytherin rivalry, who lost them the House Cup in your first year of Hogwarts despite losing Gryffindor House loads of points."
She took a deep breath, her rant subsiding a little. "In short, my House hates you and they dislike me enough already. Can you really blame me for wanting to keep my distance? If you want to speak with me, at least let us do it somewhere privately!"
Harry was a little taken aback by how passionately she had just spoken, but the rather tall first year didn't seem angry with him. Ellie just appeared exasperated by the entire situation.
"Um, well, my occlumency lessons with Snape couldn't be going worse at the moment and you said that you also took lessons, so I was wondering if..." He trailed off, suddenly it all seemed absurd. Here he was, the Boy-Who-Lived, standing outside of the Slytherin Common Room trying to convince a first year to teach him occlumency.
Thankfully, Ellie seemed to understand. "Come on, let's talk about this somewhere else. I assume you have some way of avoiding notice after curfew?"
Harry put on his invisibility cloak, causing Ellie to blink in surprise. A calculating grin spread across her face and the Slytherin laughed. "Well, this changes things. Serpentine."
Before Harry could ask how things had changed, a section of wall shifted aside to reveal the Slytherin Common Room and Ellie strode right in. With little choice left, Harry followed invisibly. The Snake Pit hadn't changed much since he had last visited three years ago, it was still underground, still had a eery green glow and was still teeming with Slytherin students. Ellie took a winding path towards the back of the common room, where study desks were cordoned off from the rest of the room by emerald green curtains.
Taking a seat, Ellie pulled the curtains closed behind them. "Don't worry, there are privacy wards on each of these booths. No one can possibly know you're here."
"I can't believe you just made me do that." Harry pulled off his cloak cautiously, he'd had a bad experience the last time he'd entered Slytherin territory.
Ellie smirked. "Sorry, I just couldn't pass up the opportunity to annoy all of the pureblood traditionalists." She noticed his expression and her smirk quickly became a glare. "What? You didn't expect everyone in Slytherin to be a haughty blood-supremacist did you?"
Harry looked away. "Are you going to teach me occlumency or not?"
"Of course," the Slytherin's voice now held a slightly hard edge after Harry refused to answer her question. "All you have to do is clear your mind."
"That's what Snape said." Harry turned to glare at her.
A mistake.
As soon as his eyes met hers, memories began racing through his mind.
"Get up, Potter."
Elowen Robins sighed dramatically. "Did Professor Snape really say all of that?"
Harry refused to say anything, avoiding eye contact as he tried to recover from his humiliation. He hadn't intended on showing her his occlumency lessons with Snape, but he couldn't exactly let her see the DA meetings or the Department of Mysteries, because that would lead to too many questions. At least he seemed to be improving.
Instead of being able to block either of his teachers, Harry had progressed to being able to divert them away from certain memories. It also helped that Ellie wasn't purposely digging for his worst moments and never seemed to take any joy in what she found inside his head.
"Of course he did." Ellie muttered under her breath, answering her own question. "Look, I don't know how he came to be the way he is, but he has it in for practically everybody and the best way to deal with bullies like that is to deny them the satisfaction of making you miserable."
"I'm used to it," Harry said, shaking his head. He'd had to deal with bullies his entire life; he didn't need to take advice from an eleven year old girl.
The Slytherin sighed again, this time in resignation. "Whatever. Just remember to practise everyday, especially before you go to sleep and when you wake up in the morning."
Harry pulled his invisibility cloak on, but paused as he went to leave. "Ellie," he stated. "You know you hate Umbridge..."
"Who doesn't?"
"Well, you know when we first met you mentioned something about standing up to her?" Harry mentally winced. This had been so much easier to say to the other Gryffindors.
Ellie raised an eyebrow at his invisible form. "I believe I mentioned a 'secret society of students that are conspiring against the Ministry Approved decisions made at Hogwarts'. So yes, I remember." A small smile touched her lips.
"Yeah, that." Harry became increasingly glad that he was wearing his cloak. "If you're still interested, then you should meet us on the seventh floor, next to the dancing trolls."
He knew what the others would think about him bringing a Slytherin to DA, but there was representatives from every house except the snakes and besides, Harry found that he trusted the odd first year. Most of the other members he hadn't invited along, so he was perfectly within his rights to invite anyone he wanted, wasn't he?
"I'm still interested in rebelling against the toad," Ellie grinned. "Count me in."