Disclaimer: I do not own shingeki no kyojin or any of its characters. I also have close to zero knowledge on cat behaviour so sorry in advance for any inaccuracies in levi'sthe cat's behaviour.
A quick thanks to ererifulon tumblr for looking this over and making sure this wasn't complete shit 3

The library is a desolate and rather lonely place after closing hours, with no one yelling at children to shut up and only making more noise in the process or nosing (in)discreetly through the erotica aisle or hiding in a corner with a laptop all day mooching off the free Wi-Fi. Eren finds it a strangely hollow feeling. He's just about finished with locking up for the night when he hears the tiniest of noises sound from somewhere behind him—

Mew.

There isn't anyone else in the library aside from himself and the security guy, he assures his inner conscience.

Mew. Mewww.

He spins around with the library keys chiming together on the loop in his hand, standing in an awkwardly improvised fighting stance in the middle of the darkened lobby. Thank god Jean isn't here, because even tipsy horses have footing more stable.

Stay calm, he tells himself, it's just the wind.

Relaxing a bit and realizing that he forgot his coat in the office (it's too late to retrieve it now); Eren sighs and wraps his scarf extra snug on his neck to make up for its absence. Tucking the keys into the back pocket of his jeans, he takes a deep breath and prepares to bolt out the automatic doors and straight to his car. It's bitter as hell outside and Eren has zero intention of spending more time there than absolutely necessary.

He's taken two long strides outside when he hears it again, this time much more distinct.

Mewwwwww.

Eren comes to a halting stop mid-step. A choice he immediately regrets, because he winds up falling on his ass on the icy cement. Icy, snow-covered, hard, cement. Fuck, his tailbone's probably busted.

On the bright side, he can now pinpoint where the sound is coming from.

Mewww.

Eren narrows his eyes. Bingo.

Carefully straightening and brushing himself off, he edges towards the drop-off box that patrons used to return books after library hours. Cautiously reaching a hand out to open the slot, Eren braces for impact. There'd better not be a bomb in there. Or a firecracker. Or living dog shit. And hell, it'd better not be—

A kitten.

A kitten.

Or a tiny-ass full-grown cat.

Whatever it is, Eren's mind goes blank.

Small.

Fluffy.

Squishy.

Whiskers.

Soft.

Cute.

"Fucking adorable," he breathes, staring at the little bundle of black fur in awe. It stops mewling to stare at him with piercing blue eyes and long white whiskers twitching, completely undeterred by the unfamiliar human that is Eren Jaeger. Said human doesn't even notice how his nose is starting to run or that his ass is beginning to really throb and doesn't even think to question how a cat even ended up crammed in a library book drop-box. All he wants in the world is to pet this miniature huddle of tiny kitty charm and obliterate all memories of masculinity he has ever possessed. There's only so much Eren's young, fragile, 19-year-old heart can bear.

He holds out a tentative hand, remembering from somewhere that you're supposed to let cats sniff you before any further action.

"H-hey…I'm Eren."

The stray doesn't move, staring back at him from within the drop-box with the most unamused expression Eren has ever seen. He shifts his weight to the other foot with one arm still outstretched, feeling (and probably looking) like an idiot.

Apparently the cat thinks so too, because it gazes at Eren's finger with a look at pure incredulity kind of like "Do you think I'm fucking stupid?"

Eren huffs. "You don't have to be so damn difficult," he withdraws his arm and studies the small animal. "It's cold. You must be freezing."

What kind of cruel person stuffs their cat into a chilled metal drop-box on a subzero winter night a leaves it alone to die?

He takes the scarf from his neck and shows it to the cat. "I'm going to wrap this around you, okay?" When it narrows its eyes at him, he adds. "So you won't be cold anymore. It's fuck—uh, freaking—freezing out here."

Wait. Cats don't know what swearing is. Eren resists the urge to throw up his hands in surrender for fear of frightening it, although at this point he was possibly more intimidated by the cat than the cat would ever be of him. It was kind of sad.

"Alright, uh, Cat—" he begins, and he swearshe sees it gape at him. "Okay, okay, sorry. But I don't have anything else to call you."

'Cat' cocks his head and paws at his neck. A collar. Of course, Eren thinks, angry at himself.

Ignoring the fact that a cathad somehow understood English, he squints at the tiny metal plate and reads, "…Heichou?

The cat meows. He takes it as a yes.

Wrestling Heichou out of the drop-box and into his car is a long, grueling battle with plenty of hissing from both parties. He knows that picking up an unfamiliar animal is a bad idea, but 1) Eren doesn't have much other choice, 2) this cat's got more spunk than he's ever possessed in his life, and 3) his ass doesn't hurt anymore but that's only because it's going numb from cold, plus he forgot his coat so all he's wearing is a hoodie and jeans.

He ends up wrapping the black bundle of fur in his scarf and plopping it in the passenger seat with the seatbelt on just in case.

"So, uh, Heichou," Eren begins, starting the ignition and pulling out of the parking lot, "How'd you end up in that return box anyway?"

The cat doesn't respond. Eren feels it staring at him and struggles to keep his eyes on the road.

"Um…" Well, what was he supposed to say? "Are you a guy or girl?"

Damn. That came out wrong. "You're…female?"

The cat growls a small, cute but mildly frightening growl.

Okay, so according to the cat, he was male.

There's awkward silence for the remainder of the drive.

The trip from Eren's car to his apartment is another agonizing battle. Heichou doesn't seem to like being picked up, and turns out he's pretty feisty cat. Feisty as in tiny, angry and murderous.

Eren manages to barely make it through the front door before Heichou uses his arms as a launch pad and lands primly on the nearby loveseat. Eren shakes himself all over and tries to regain a sense of feeling in his arms, legs, face, and butt. Hadn't he decided not to stay outside for longer than necessary?

He notices Heichou settling on his haunches and observing his shake-out session intently. It's more than slightly unnerving.

He decides to ignore the cat's piercing gaze and busies himself with finding a bowl and some leftover cat food (thank god Mikasa had had him do some cat-sitting a while back).

"Here," he sets the dish on the ground, along with a cup of water, "Eat if you're hungry."

Eren leaves Heichou with the food and goes to get him a towel. When he gets back, the cat is glaring at the food dish like it personally offends him.

"What is it now?" Eren sighs. It's cold. It's late. He just wants to sleep.

Heichou hops off the couch and makes an exaggerated show of pushing the dish away from him with one paw.

"You…don't like cat food?"

The cat sticks out his tongue.

"Alright, alright. But I'm not making you anything else. Starve if you want." Eren yawns, turning around to go back to his bedroom. "I'm going to bed. You can sleep on the couch or whatever."

The cat rolls his eyes—wait, what?—and bounds back onto the loveseat, curling into a ridiculously cute ball of black fluff. Eren resists the urge to 'aww'because that wouldn't be manly.

-x-

Later that night, when he's sure Eren must be asleep (feline senses come in handy at times like these) Levi sneaks into the bathroom to do his business.

Cats need litter boxes, and that idiot had completely forgotten. If Levi were a real cat, he'd have pissed on the carpet by now.

It's thanks to Eren that he isn't freezing his balls off in that library return slot, though. He gives him credit for being stupid enough to approach a stray—and being even stupider by bringing it home with him.

I'll stay here until I get to pay him back, he decides.

Even if this brat's place is fucking disgusting. Having an exceptional sense of smell doesn't help.

as you can probably see this will be a purely lighthearted fic with minimal angst and pain, so expect more cat!levi shenanigans :D

thank you for reading! i'm always looking to improve, so feedback would be greatly appreciated :3

my tumblr is rivaidere, feel free to message me with any questions/suggestions!