So Smile:

(OOCness ahead)

("I want it to be angst filled it should be about Percy as a serial killer and Nico as his accomplice." -Ed Sheeran's Fangirl

CHALLENGE ACCEPTED)

. . .

Annabeth saw them walking down the street again today.

Perseus Jackson and Nico di Angelo. They were roommates on an expensive looking flat near her home. To anyone's eye, they were the image of perfection. Too perfect for Annabeth's taste, but they were still charming. She smiled when Percy tipped her hat at her, and that warmth broadened when she saw a tentative looking Nico follow the same steps. The florist's muscles in her cheeks were still jumping after they had left, and Annabeth fluffed her flowers appreciatively.

Two days later, she would join them for dinner.

And one week later, her body would be found in a nearby river.

. . .

He was up earlier today.

Nico was groggy with sleep, but he still managed hear the light thundering sounds of Percy's steps walking up the stairs. The twenty year old let out a sigh of inconvenience and curled up tighter in his small bed, grasping his bony knees with shaking hands. The man wanted to chide himself for acting so childish. He wasn't allowed to do this. He was older, shoulders wider and knuckles harder. He was filled with the aspect of maturity and responsibility, something that now he couldn't simply pass off. If there was something that needed to be done, he had to do it. There was no beating around the bush or procrastinating- if it was needed to be accomplished, it was his job to complete the problem. If not, there would be consequences.

No. Nico's vision blurred at the word. Consequences. He couldn't think about the pain inflicted upon him if his 'simple' tasks had been led astray.

He squeezed his eyes shut harder, trying to stop how hard he was trembling. Percy detested weakness. He didn't believe in casting emotions aside, ("Emotions are inevitable. They can't be dismissed on command") but he did believe in hiding emotions. Hiding weakness. Slamming the sadness and the shame down, swallowing it behind a thin mask that was always persuasive and angelic. Because, after all, who would believe that two charming young men were capable of murder? No one. Percy would smile at random citizens, displaying unordinary acts of kindness, and the elders that had lost faith in humanity would feel a spark of hope as Percy's green irises lit up in vibrancy. Smiles, smiles, smiles. Percy had lectured Nico about this a variety of different times. The smile had to be perfect. It couldn't be too snarky, and it most certainly couldn't evolve into a grin of sickly patronization. The smile couldn't be too bright ("If it's capable of blinding the sun, then it's wrong") nor could it be too perfect. People were suspicious of perfection. They were envious of perfection. The smile had to falter a little, to show the humbleness it beseeched, and a lingering hesitance had to accompany it.

To Percy, the mask was what tied everything together. The mask was what led the unsuspicious police away from their front door and to another's. The mask was what made the women of the street willingly follow the two home. The mask glued together all the ends that most killers had problems with. Most of them were driven by lust and excitement, too rash and incapable to smother their feelings. Percy didn't fall into the 'most' category. He spent more time on the mask than he did the actual killing. Evidence was meaningless to Percy. ("Let them find it. Let them gain proof that I killed. Then let them take me to court. I'd win over that judge and jury before the defendant could even could say 'guilty'.")

Percy spent hours on the precision of the mask. He painted on a smile-one that wasn't too wide and wasn't too small-two bright eyes which were filled with empathy, and cheeks that were easily flustered by even the smallest of compliments. That mask was an angel among men.

But it wasn't real.

It was made with material, not with truth.

Nobody was better at wearing a mask than Percy.

That was what tricked Nico in the first place.

Percy deceived him with those trusting eyes and understanding smile.

With a small sigh of awareness, Nico turned on his side.

Maybe he should feel thankful Percy saw potential in him. The man often never did. He tried to feel any sense of gratitude. Nico reached deep down, past all the screams of endless victims and acts of senseless crimes, and tried to find a flicker of contentment. It was lacking. All he could feel was a hollow emptiness where his humanity should be, and a burning resentment for Percy. For Percy; the man he was supposed to love. For Percy; the man that had 'saved' him. For Percy; the man that had given Nico something he craved for his entire life: purpose.

Ultimately, it came down to entrapment.

He couldn't leave. He was trapped. Nico was too far in to call it quits. He had dug himself a hole (or perhaps it was his grave) and it was too deep to simply crawl out of. Nico was drowning in images of bloodied victims and the acknowledgement that he would have absolutely nothing if he left now. He had no family left, nothing to go back to. Maybe it would've been different if he had left earlier, or if his sister was still alive and waiting for him eagerly with accepting hands. But Bianca had died a long time ago at the youthful age of twelve. Her fragile body had been trampled to death by a carriage's wheels and the hooves of strongly built horses.

Their mother was somewhere out there still, or so Nico hoped. A weaker side of him still longed for the ginger touch of his compassionate mother's hands. She had been ridiculed because of the wedlock that had produced Bianca and eventually cracked under the stress. Maria left Nico and Bianca in the care of their father, Hades, who was caring, but distant and cold. He died from yellow fever months later, and the two were cast out into the streets. Bianca got a job in a factory and struggled to keep Nico alive, but failed to see to herself. She hadn't looked both ways crossing a busy street, stolen bread tucked underneath her tattered coat, the owner of the bakery chasing her.

And that was the end of his sister.

Nico stared up at the ceiling with blank eyes. He was still in the outfit from the night before, not bothering to peel off the sweaty and bloodied clothes. Percy was calling for him, a sense of delight to his tone. He tried to remember that it was Percy that saved him from his pathetic life on the streets, the place where he lied and robbed for food. But remembrance did nothing, and he could feel nothing other than a strong sense of animosity. ("There will be times when you feel hatred towards me for what I request you to do. Our work is dreadful indeed, but necessary. Someday you shall thank me.")

There had been a time when he trusted Percy's words and took them all to heart. Nico always listened intently, thrilled at the prospect of finally gaining something other than nothing. Of course, his feeling of elation didn't last long. The way Percy spoke about murder made it seem like some contrived fantasy rather than reality. He spoke like it was a fairytale, eyes gleaming and the muscles in his lips twitching. Nico was horrified, but laughed it off. Percy enhanced his laughter by planting hard kisses on the corner of his mouth. Nico was soon drunk on the idea of Perseus Jackson. On the very idea of finally (finally) having a home.

The perfect world that Percy had strewn soon fell apart at the tendrils.

They had been walking home after a night out, Percy in his dark trench coat and tall hat, Nico in similar wear. They didn't kiss in public, nor do anything that Nico so longed to do. It just wouldn't be accepted, so the two men were reduced to waiting until after they were locked in Percy's house with the blinds down.

Nico stared harder at the ceiling, blanket tucked snug around him. Percy's footsteps were growing closer, but the memories wouldn't stop playing against his obsidian eyes.

They had been walking home.

A woman had been on the street corner, dressed in blue and scarlet. Her hips were large, breasts plump, capturing the curves and tightened fabric of her dress. Red fiery hair was down in frizzed curls, cigarette clad in her hand. She looked hardened at first, but those big eyes instantly changed his opinion. They were wide and green, full of child-like innocence that he never seen before.

Percy had paused that night, glance zeroing in on the woman. Nico had froze when he had, blanching so slightly. They hadn't actually spoken about what went on after the blinds were pulled down, and he had been surprised at the look Percy had sent the woman. It made Nico's cheeks burn again, but this time not with gratification.

"Percy? What are you doing?"

"Just a moment," he had replied.

Percy sauntered over to the girl, and Nico, too confused to do anything else, followed right on his heels. "What is your name, miss?"

"Rachel Elizabeth Dare, sir." She did a little mock curtsey, hair whipping over her shoulder as she knelt down. She reeked of strong perfume and cigars, but it wasn't unappealing. Percy's smile was cast down on her, but it wasn't kind or charming. It was sickly sweet, and the lines were so deep that it could've cut his cheeks.

Nico had paled further from beside his companion, all his tipsiness fading quickly.

Percy turned around to look at him. "She's perfect."

"For what?"

Rachel had giggled loudly at Nico's question. "What do you think?"

He knew what her job profession was. He knew that the skimpy dress and colors of the night weren't coincidence. He felt a sense of dread knot in his stomach at the misconception. Percy hadn't realized that Nico only was interested in men, and Nico felt anxious. He really should've explained it to him earlier, but thought that it hadn't been necessary or immediate.

"Percy, I-"

"Not for that," he had replied in a smirk. "Remember what we discussed earlier?"

They had spoken of multiple subjects earlier, but only one was bothering him. Did you ever wonder what it would be like to commit murder? That innocent conversation about employment had strayed to that, and Nico found himself sweating underneath his thick overcoat.

"Percy, with all due respect,, I think we should go."

"Not yet."

Rachel had smiled further, her big eyes still innocent.

"Nico?" Percy called from outside the bedroom. "Are you awake yet? You're sleeping the day away!"

Nico shuddered underneath the covers, ripped from his memory of the girl with red hair. He shut his eyes, praying that Percy would just go away. He needed to decide what he was going to do. The common answer would be to go to the local authorities, but this wasn't a common situation. Nico didn't have anywhere else to go. This was his home. It had been for the past six months. Even after Percy slit the girls throat in front of his eyes, he still remained here.

He had helped him hide Rachel's body.

Nico himself had aided in Percy's disposal of the girl with innocent eyes.

The door clicked open. Nico stiffened, muscles tensing.

Percy was often too caught up in his emotions and facade to worry about the evidence left behind. He knew it was vital, but Percy didn't have the patience. So that job fell into Nico's hands. It was his responsibility to get rid of the murder weapon. It was his responsibility to swipe any surfaces where Percy's fingertips lingered. It was his responsibility to do a thorough sweep of the area. If he failed, if he overlooked something, then there would be consequences. ("I'm disappointed in you, Nico. You were sloppy and careless. You know I don't like to hurt you, but pain seems to be the best motivator to you.")

Over and over Nico did his job.

Over and over he watched Percy cover up suspicions with a smile.

Every night Percy would work on his collection of mask, adding touch-ups and gluing back together pieces when it began to crack and break. ("You must understand how this works. If you pretend to be something for long enough, you become the thing you were pretending to be.")

Nico curled up tighter, almost into a ball, hands trembling underneath the pillow. He had been reduced to a child in a matter of seconds. He could feel Percy's gaze on him, hard and undecided.

What he didn't understand, what Percy couldn't possibly realize, is that when the time came to remove the mask, he couldn't do so without removing a bit of his own skin.

("Do your job well, Nico. If you don't, there may come a day where your services won't be needed any longer.") Percy knew how to establish fear. He knew how to make it come alive so it wasn't just an emotion anymore, but a monster. A living, breathing, monster that had its claws around Nico and wasn't just content on merely letting him go.

Percy was still standing there.

So many smiles.

So many masks.

Eventually, it was just hard for Nico to keep up. Those painted on faces all blended together with tight smiles and bright smiles and flushed smiles and cruel smiles. Which was the real Percy? Was he even human anymore? Was Percy gone and replaced with one of the masks he created? Was he nothing more than a smile? Was that all his existence thrived for? To be someone he wasn't? To deny, deny, deny with smiles, smiles, smiles?

When did Nico start to be unsettled by his companion? What day had that been?

An accident, he had claimed it to be after Rachel's death. I did not intend to kill her.

Deep down, Nico knew he had been lying. It's okay, he had replied to his hysterical friend. Don't worry. I'll take care of it.

Even then, he had dismissed Percy's condescending smirk as a grateful one.

So when had Nico started growing afraid of him?

Was it that one time he held a gun to his forehead? Or the other time where he threatened to slice off a finger?

Or maybe it was just his tendencies to brutally murder women.

When had that become Nico's normal?

"Nico?" He could feel the mattress dip as Percy rested his weight on the other side. He could smell him-the scent of salty air, tobacco, and a distinct metallic substance he couldn't place- and hear his steady breathing. They held a slight tremor, but that could easily be mistaken for enthusiasm. That's what everyone else assumed when they caught glimpse of that angelic smile. There was a soft prod to his arm. "I know you're awake."

Nico's breathing hitched at his words, and his fingertips pressed into the mattress.

"Do you feel ill?" he questioned, a hand gently resting on his shoulder. Nico tried not to flinch, but surely Percy could feel the fear radiating off his body. He could probably hear his heart beating. When the younger man didn't respond, he sighed. "I'm just wondering if you remember where your loyalties lie."

("Betrayal is something I never forgive, nor forget.")

At the suppressed memory, Nico shuddered. He hoped Percy would blame it on the cold winter air, but then again, he had never been lucky. Nico di Angelo's entire life revolved around the notion that he was unwanted. His father looked upon him as an inconvenience, his mother was too frail to even cast a gaze, and the rest of his family sneered down at him with disapproval. Wedlock had tarnished his name, and it left him alone. Bianca, his beautiful sister, the one person who accepted him, had died.

But then Perseus Jackson came along.

He gave Nico light again. He showed Nico that the world was not always cruel.

He gave Nico hope with those smiles, only to steal them away.

There wasn't any choices to be made.

("There's always a choice.")

Lies. All his words were lies. His lessons, his personality, Percy's smiles- they were nothing but a painted mask.

He hated Percy, but Nico hated himself even more for falling into the web Percy had weaved. He was tangled and trapped, forever to be there until his old companion decided that Nico was a nuisance.

And then he'd be unwanted again.

"No, of course not," Nico dismissed, coughing hoarsely for good measure. His tears and silenced sobs from the night before made his voice sound thicker. "You're right. I don't feel too well."

The shifting figure stilled. Percy smiled sympathetically, eyes shining with concern. "How dreadful. I'll make you some tea." He leaned over so Nico could smell him-ah, blood. That was the metallic scent he couldn't place- and planted a soft kiss on his temple.

Nico held his breath until the door had closed behind him.

Then he let out a repressed cry, tears clouding his vision.

The endless victim's screams wouldn't leave his mind.

Maybe it was his turn to get a mask.

("Smile, Nico. You're finally home.")

SO SMILE

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Even the BRIGHTEST smiles can hide the

DARKEST

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A/N: Okay. It's official. I AM AN EVIL PERSON. Er...I hope you liked reading this? It's quite different from things I usually write, and I actually enjoyed writing this a lot. If you didn't know already, you guys can request one-shots you'd like to see written by me.

Ed Sheeran's Fangirl: Hopefully this is something you enjoyed...hopefully...xD

Reviews are always appreciated, and please excuse any grammar errors I may have made.

(I'm also aware of the mega, extreme OOCness of Percy and the rest of the characters)