So, this is my first ever Attack on Titan/SnK fic. Let's hope this goes well, why don't we?

Disclaimer: I do not own Attack on Titan/SnK

K is for Key

Eren glanced furtively around the empty hallway from Corporal Levi's bedroom door. The man himself was still fast asleep, his face buried in Eren's pillow, his body spanning both sides of the bed. The sounds of waking squad members filled the hall, making Eren's nerves jump erratically. He needed to get back to his room in the basement without being seen before anyone could make it out of their rooms, especially Mikasa or Hanji. He shuddered to think what either of them would do if there was so much a hint of what really went on behind Levi's closed door.

Taking a deep breath, he closed the door silently and took off at a fast clip. Silently, he prayed to whatever god(s) or goddess(es) watching them that he would not run into anyone.

Though he'd never believed such a being was real, after several eternal minutes, he was delivered to his room without so much as a door beginning to creak open as he passed it. Quickly, he changed into clothes that did not smell of a certain Corporal. Thanks to the man's OCD about all thinks clean though, he'd taken a bath after their aggressive, sweaty lovemaking, washing the man's scent from his skin for the most part.

The memory wasn't as easy to wash away though. He could still taste Levi on his tongue, feel Levi's hands roaming his body, feel Levi's tongue taking advantage of the sensitive skin on the back of his neck, feel Levi pressing in between his legs-

Eren cut off his thoughts, his body beginning to react to the remembered sensations. Gasping quietly as the material of his pants rubbed against him, grinding his teeth against the sensation, he finished dressing and ventured upstairs for breakfast.

…..

"Hey, Eren," Armin said suddenly, sitting across from the distracted teen.

Reluctantly tearing his eyes away from Levi's perfect ass that was encased in those white pants that hugged him just right, Eren hummed, "Hm?"

"Where is your key?"

"What?" Eren asked, confusion pulling his eyebrows together.

"Your key, where is it? It's not around your neck like usual," Armin explained, pointing to the exposed skin of his chest where usually you could see the string that the key hung from.

Immediately, Eren's face drained of color, going ghostly white as he began to violently choke on the chuck of bread he'd just ripped off. His eyes watering, they jerked to Levi who was now watching Connie and Mikasa take turns slapping his back with a small margin of curiosity. When they're eyes met, Eren started choking even harder.

Around the man's neck, just visible under his collar, was the string Eren's key always hung from.

'Shit!' Eren thought, wracking his memory to remember when the exchange could have possibly occurred. Cheeks lighting up like paper soaked in starter fluid, he finally landed on the moment only a few hours prior.

Usually, Eren would have no problem seeing Levi's face during their little romps, but tonight, his key seemed expressly determined to infuriatingly obstruct his view. Sighing in frustration, he shoved it over his shoulder for the fiftieth time.

"Take it off," Levi ordered, staring up at him with as much annoyance as he was feeling. 'Technically' he was allowing Eren to top for the night, but if he didn't fix the problem soon, he wouldn't be allowed to top in any fashion whatsoever.

Pulling the key over his head, Eren stared at the small piece of metal, trying to decide where to put it. Finally, his just slipped it over Levi's head, letting it rest between the smaller man's collar bones. "This way I know it'll be safe," he explained when Levi shot him a questioning look.

"Shit," Eren repeated, this time aloud, through his coughing.

"What? What's the matter?" Armin asked, his anxiety firing up, "Did you lose it? Where did it go?"

Mikasa watched him intently, her eyes slowly following his line of sight. Her hand still slamming against his back grew progressively more aggressive though her face showed none of that.

Eren jerked his eyes away from Levi, not needing her to get any ideas, good or bad. Sucking in a shaky breath, he forced down more coughs. "Nothing, nothing. Just for a second, I forgot where I put it, but I remembered. It's in my room. I should probably go get it. Yeah, I'm gonna got get it," he said, his voice hoarse, words just spilling from his mouth. Leaving his food half-eaten, he jumped from his seat, hurrying past Levi. Out of the corners of their eyes, they made eye contact and held a silent, second-long conversation. Levi nodded almost unperceptively.

The teen breathed a sigh of relief, jogging towards his room. Before he could make it there, Hanji stepped into his field of vision, blocking his path. "Oh, hello Hanji…" he mumbled, eyes wide, his heart sinking through the floor and completely disappearing.

"Well, hello there Eren," she shouted in a voice that should have been her outside voice, "I was wondering if you'd like to help me with a new experiment as your training today?"

"Well, actually, I have this thing-"

Hanji cut him off, grinning and grabbing his wrist. "Of course you would! Unless you're going to meet a secret girlfriend. Speaking of which, where is your key? You always have it." She grinned at him knowingly, her eyes sparkling with mischief and curiosity.

Sighing, he gave in. He really didn't want nor need Hanji on their scent. She already seemed to suspect which was almost just as bad. Levi would be pissed at him later, but at least he had a reason. "What did you have in mind this time?" he asked, ignoring her question.

…..

Eren was roughly shoved up against the wall, his head spinning from both the impact and the side effects of the experiment Hanji had put him through for more than a couple hours. She'd wanted to see if with his Titan super healing ability he could withstand any poison she drugged him with. Of course, all of the poisons had had anecdotes in case his body couldn't expel or neutralize them, or at least that's what Hanji had told him. His body had indeed done that and more, though it had come at the cost of copious amounts of vomit and a few blackouts.

"What the hell was that, Jaeger? And why the fuck do you smell so hideous?" Levi snarled, his nose scrunching up in disgust.

It would have been cute and Eren would have taken the opportunity to kiss him if 1) There weren't others watching the display, 2) If his head hadn't been violently spinning to the point that it was hard to see, and 3) If he hadn't been about to dispel the crackers and water Hanji had forced down his throat.

Struggling weakly against much stronger hands, Eren whispered, "Hanji. Experiment. Oh god, I'm going to puke!"

Levi jerked back like someone had screamed snake, allowing him to drop to the scarce grass. He heaved several times before the foul liquid actually spilled from his mouth.

"Ah shit. Eren!" Levi shouted, forgetting about their surrounding squad members for the moment. Staying as far from the vile smelling liquid as he possibly could, Levi placed a hand on Eren's back, rubbing gentle circles between his shoulder blades. "Someone go get Hanji, now!" he ordered without looking up.

Within moments, Levi could already hear Mikasa shouting, "Eren!" Her voice was accompanied by several of the others'. In no mood for the black haired girl to touch Eren, he pulled the boy to his chest before he could slump into his own vomit.

Despite sounding the closest, Mikasa was not the one who made it to them first. Armin arrived on the scene, breath coming quick. "What happened, sir? Is he alright?" he asked, frantic.

"I don't know," Levi admitted, shifting the teen's weight in his arms, "Help me get him up."

Armin obeyed immediately, taking the brunt of Eren's weight until the man who ranged about the same size as him could get to his feet. Once up, he scooped Eren into his arms without even a grunt. Armin stepped back in surprise, watching his every action carefully.

"Hanji, what the fuck did you do to Jaeger this time?" Levi spat, moving around the puddle of vomit to meet everyone running to check on the teen. Among them was the scientist, sheepishly grinning down at him.

"Sorry, I might have overdone it with the experiment I conducted today," Hanji explained, "We should get him to his room."

"You think?" Levi asked sarcastically.

Mikasa watched the Corporal with narrowed eyes as the pair hurried into the safety of the castle walls.

…..

Armin stood by the door, waiting for Hanji and Levi to leave so he could go in and look after Eren like he'd been asked to. Mikasa had been sent away to do a complete perimeter check because she was utterly too loud and nosy from Levi's liking.

"I'll come back in a few hours, maybe around midnight," Hanji informed him once she'd come up the basement stairs, "You should probably just wait here until Corporal Levi comes back up of his own accord. It shouldn't be long now." She smiled like she knew a secret he didn't, which was probably the case, as she headed back to her lab, patting him on the shoulder.

Armin stared after her in confusion. 'What was that for?' Sighing, he allowed his mind to wonder exactly what Hanji was hiding. He waited a long twenty minutes before he began to worry.

'Should I go make sure everything is alright? Make sure Corporal isn't strangling Eren in his sleep because he puked on him? Maybe he left and I didn't notice? But Hanji told me to wait… No, I should go check.' Decided, Armin silently followed the stairs down into Eren's chambers. Peeking his head around the corner, he nearly gasped in surprise.

Levi was leaning over Eren, his lips pressed to the teen's forehead. Hanging from the front of his shirt, off his neck, was Eren's mysteriously missing key.

Face burning as if he'd been peeping on two of his teammates doing the do -like he'd accidentally done once with Marco and Jean- Armin crept back up the stairs to wait and agonize over what he'd witnessed. Levi followed him up soon after, not five minute later. Staring at the older man with wide eyes, he screamed in his mind, 'Dammit! Son of a bitch! If I'd only waited three more fucking minutes! Three! I wouldn't have seen that private moment! Fuck!' He'd never cursed so much, whether in his mind or out loud, in his entire life.

"Arlert!" Levi barked, bringing Armin's attention back to reality.

"Y-yes?" Armin squeaked, standing at attention.

"Watch after him," he said simply, turning and disappearing down the hall.

When his footsteps had faded, Armin cried, "I'm so confused! I don't understand!" ruffling his hair vigorously.

…..

Mikasa had hurried through her boarder check, even though it'd still taken several hours, taking Armin's place by Eren's side forcefully, shoving the blond from the room. Hanji had already stopped by for her midnight check-up leaving her alone with the recovering teen. She'd already been there for an hour, and after searching through all his belongings, through every nook and cranny, she still hadn't found the location of his key.

"That stupid little shorty must have stolen it," she snarled, brushing hair from Eren's forehead, "Don't worry, I'll get your key back for you. I promise." She kissed his warm skin gently, unaware of the fact that the lips of the man she hated so much had already been there.

…..

"Mikasa! Jean! Oh my god!" Armin cried the next afternoon, barreling towards the pair who had managed to exit the castle at the same moment. They looked like stone gargoyles, their faces set in scary lines.

Jean's mask crumbled first and he stared at the small blond. "What happened? Why are you freaking the fuck out? And do you know where Eren's key is? I keep hearing that he lost it somehow."

"That's what I'm freaking out about! I figured it out!" Armin shouted, flapping his arms, his clear blue eyes wide.

"I… don't understand," Jean admitted.

Slowing down, Armin inhaled a deep breath. His voice dropped as he said, "I think Corporal Levi and Eren are in a secret relationship."

Mikasa and Jean stared at him for a long moment before Jean broke out in laughter. "Armin, what are you on? Those two? Fucking? That's ridiculous!"

"You don't understand!" Armin protested, pushing down the sassy retort he'd been about to spew, "When I went to keep an eye on Eren, I had to wait until Levi left before I went in, but he wasn't coming out so I went in to check on them. I saw him kissing Eren's forehead and Eren's key was hanging out of his shirt!" His voice had dropped to a conspiratorial whisper, trying not to be overheard by prying ears. "Eren would only let someone he trusts with his life hang onto that key, and no amount of force would make him hand it over. Corporal Levi isn't one to steal either." He shot a glance at Mikasa who wouldn't meet his gaze, knowing that was exactly where her mind had gone.

Jean shook his head in denial. "You've got to have it wrong. Levi is thirty-something-years-old and Eren is only fifteen. Isn't there some law against fucking a minor, especially one where you are twice their age?"

Armin just stared at him like he was the stupidest person in the world. "We get eaten in droves and are fighting against the extinction of the human race, while trying to preserve what little territory we still have left. Even if there was a law like that, do you really think they would give a shit? 'At least one of them can't get pregnant' would probably be their whole reason for leaving the relationship be."

Jean shook his head again. "Even so, I'm sure you've got it wrong. I'm going to find out and prove you wrong. Oh, speak of the devil, there goes Eren looking sneaky." Turning, he headed in the direction the other boy had disappeared in. After a good night's sleep and some food, Eren had been good as new.

"I'll help you," Mikasa offered, following after him and ignoring the pointed glare Armin shot at her.

…..

Eren glanced this way and that, checking to see if anyone was following him. His search turned up empty, but he swore he could feel the eyes of one young black-haired woman boring into the back of his head.

Sighing, he moved closer to the door, ignoring the little voice in his head screaming that this was a bad idea. He knocked lightly on the door. "Come in," he heard the voice that had groaned his name more than a day ago, call. As he pushed the door open and stepped into the room, a mass of still drying, just bathed Corporal hit him square in the chest, thin yet strong arms stringing themselves around his neck.

"Close the door," Levi ordered, wrapping his naked legs around Eren's waist, the key swinging from his neck. Eren, without protest, kicked the door shut, carrying the near vibrating man to the bed.

…..

"Oh my god," Jean whispered, eyes wide as he stared down the hall at the door Eren had just disappeared through. They hadn't seen the blatant show of lust and affection, but they could already hear a moan from the occupants. He wasn't sure, but he thought the voice sounded like Eren's. "They are fucking. Armin was right! How haven't they been caught yet? They aren't even hiding it all that well!" When his question only received silence, he glanced toward his companion.

Her face had reverted back to stone. "I'm going to murder that shorty," she whispered in a dangerous voice, a voice that promised for things to be torn off. She took the first steps toward doom before Jean clamped his arms around her middle. "Hey Jean, did you know that it only takes around twenty-four pounds of pressure to rip off a guy's dick? Want to test that theory?"

"No! You can't! He'll kill you if you walk in on them!" he shouted in a whisper, pressing his face into the hollow of her back.

"I don't care," Mikasa replied tersely, struggling against his strong hold to inch her way towards the door.

"Mikasa! Please! Think rationally!"

"I am thinking rationally. I'm rationally thinking of how best to murder that shorty that'll cause him the most pain," she told him calmly, beginning to draw her swords, "Or how to castrate him so he can never screw another human being in his short little life."

Jean frantically tried to think of a reason that would keep her there. "If you get imprisoned for attacking a senior officer, who is going to keep Eren alive? You can't do that from prison," he explained.

Coming to a halt, Mikasa ground her teeth. He was right. She hated when people actually made sense. It always made things so much more complicated than they needed to be. Suddenly, she turned on her heel, dragging Jean along behind her.

…..

"Did you hear?" a young woman asked close to Armin, Mikasa and Jean's table. The three stiffened, tuning their ears to the conversation. The woman grinned at her friends surrounding her, shaking her fists in excitement.

"Heard what?" a male voice asked.

One of the other women blinked slowly at the man, "Obviously you haven't heard then."

The first woman waved her hand at the other, rolling her eyes towards the ceiling. "Eren and Corporal Levi are in a relationship! They're doing it!" the girl gushed, bouncing in her seat like a puppy on speed, "I heard that if you stay up long enough, you can hear them, and they're so loud!"

"What? No. Are you serious? Those two? I would never have pegged Eren for being gay! I was sure he was a straight man."

"Right?!"

Jean glanced at the other two who were at his table, quirking up an eyebrow. "I guess more people suspected than we thought," he mumbled, scratching the back of his head, "I wonder what other rumors are floating around this place."

Armin sighed, dropping his head into his arms. "I guess, and I really don't want to know. I can just imagine what is going around about the rest of us relatively new recruits."

Just that moment both individuals being gossiped about walked through the door. Nearly every conversation in the dining hall came to a screeching halt, though neither seemed to notice.

Both looked utterly relaxed for once in their lives, their shoulders untightened. Levi growled something under his breath at the younger male that had Eren laughing. He grinned, sticking his tongue out at the older man childishly. Still hanging around Levi's neck was Eren's key, tucked beneath his shirt, but visible through the thin fabric, quickly cementing what had only been gossip in truth.

Well, there you go. Hope you enjoyed my first Attack on Titan/SnK fic. I'm hoping there will be more coming soon.