Isaac has never had any intention of getting a pet, but in the end he has no real power over the decision when it happens.
Derek sends him to pick up a box from Deaton (Isaac honestly doesn't ask about the contents of the box; he'll find out soon enough, and it will probably not mean anything good) so he goes to the vet clinic and stays for a while to hang out with Scott while he does the rounds and checks on all the animals in the vet's care. Isaac follows Scott around the clinic, sticking his fingers through the wire of the cages to ruffle the dogs' fur and let the cats lick his fingers while Scott checks stitches and rewraps bandages.
Scott spends a long time at one of the bigger cages near the back and Isaac wanders over before he finishes, peering in over Scott's shoulder to see what he's doing. There are a bunch of cats inside—or rather, there is one cat and a handful of kittens suckling from her. They're adorable, Isaac thinks—the four tiny, brown and white balls of fluff. And then he sees Scott's hand nudging in between the kittens, not pushing them away from their mother but making space before gently placing something down. It takes Isaac a moment to realize it's another kitten, this one smaller than the rest and mostly white with its left ear and front right leg mottled the colour of caramel.
"C'mon little guy, get in there," Scott says quietly, nudging the kitten gently forward. It seems to make an effort, shifting towards its mother until the others move, blocking it once again from its food source. Scott frowns, watching the kitten make another half-hearted attempt to butt in only to be rebuffed by its siblings. He reaches back into the cage and carefully picks up the kitten, holding it up at eye level. "You just gotta fight for it a little," Scott says, sighing. The kitten mews in his hand, the sound tiny and high pitched and a little heart-breaking, and Isaac reaches out without thinking to scratch gently behind the kitten's ear. It mews again, rubbing its head lazily against the pressure. "You want to hold him while I make up his food?" Scott asks.
Isaac hesitates for a moment before nodding even though Scott is already taking his hand and manoeuvering them to hold the tiny animal. The kitten settles happily in his cupped hands, soft and warmly alive as it snuggles down. It feels oddly comforting to have the kitten in his hands; the closest thing Isaac can compare it to is a hug—the warm comfort of another living being. It's a feeling Isaac hasn't had a lot of in his life.
When Scott returns, he has a bottle in his hand and he automatically reaches out to pick up the kitten. Isaac feels a momentary sense of loss at the thought of it being taken away; it must show in the downturn of his mouth or some flicker of his eyes because Scott pulls his hand away and offers Isaac the bottle instead, holding it out until Isaac takes it from him.
They work in silence for a few minutes, Isaac feeding the kitten and Scott continuing his rounds to the other animals. Isaac watches the kitten for a few minutes and then lets his eyes drift over the room, watching how attentive Scott is with the animals, his attention returning to the tiny critter in his hands only when he feels the rough, wet drag of the kitten's tongue on his fingers. He smiles down at the kitten, and his head fills with images of taking the kitten home and lying on the couch with it asleep on his stomach until it grew hungry and licked at his hands until he fed it.
He's never really had any desire for a pet before, but maybe, Isaac thinks, that's a product of never before having had a home that he would even briefly consider bringing another living creature into. It's still impractical; Derek doesn't particularly strike Isaac as the type to like adorable, fluffy (ok, shedding) animals wandering around his place. He chuckles a little at the thought of Derek's reaction when he sees the kitten, a mix of broody and resigned with some half-hearted threats thrown in. He's still picturing the scene and doesn't even really register that he's asking Scott a question until it's already out of his mouth. "So, who do they belong to?" Scott glances over his shoulder, a confused look on his face. "The kittens I mean."
"No one. Or, well, the clinic I guess?" Scott says. "Someone found the mom hiding under their porch when she was pregnant, and they brought her in." Scott closes the cage he was working at and turns, eyes landing on the kitten in Isaac's hands. "That one," he says, jutting his chin briefly towards Isaac to indicate the kitten, "probably wouldn't have made it otherwise."
Isaac unconsciously shifts the kitten closer to him, holding it curled against his chest with one cupped hand, feeling suddenly protective. "But he's okay, right? Even though he's small?"
Scott nods, watching Isaac watch the kitten. "Dude, I don't think Derek is going to let you have a cat in his loft."
"What? I'm not adopting a cat."
"Ok, sure," Scott says, laughing lightly, "but that little dude has already adopted you, so ..." The kitten chooses that moment to but its head against Isaac's chest, and Isaac looks down at it, a smile growing on his face. "But if you're sure," Scott begins, stepping towards Isaac, hands extended towards the kitten, "I'll just put him back in the cage."
Scott hasn't even touched the kitten before Isaac is relenting, unconsciously taking a step backwards away from Scott. "Okay, fine. But if Derek kicks me out because of this, you had better expect me and Snowball here to appear at your door looking for a place to stay." Again goes unsaid—it's among the latest entries on the list of things the group had silently agreed never to bring up.
"How do you know that's not what I'm hoping will happen?" Scott asks, and Isaac gets distracted by that for a moment until Scott asks another question. "Also, Snowball? Really?"
"What's wrong with Snowball? What, am I supposed to name him after you?"
"That's not what I—"
"Actually that's not bad!" Isaac holds the kitten up and speaking directly to it. "What do you think, Scotty?" Scott makes a disgruntled face, but Isaac shoots him a grin and the slight glower dissolves almost instantly into fond resignation.
"Why don't we go out to the desk and I'll get Margie to start the paperwork so you can take the kitten with you when you go."
"He has a name," Isaac says, knowing full well that he's being a little shit and that Scott will go along with it anyway, "and it would be polite to use it."
Scott sighs, and manages to sound only slightly put out when he speaks. "Fine. Why don't we go get the paperwork started so you can take Scott home with you."
"Okay," Isaac chirrups, smiling brightly again now that he's gotten his way. He lets Scott take, well, Scott from him (and Isaac is just now realizing that this might get confusing rather than just being hilarious and maybe just a little meaningful) and then lead him out to the desk so he can willingly sign over his life to an adorable ball of fluff.
As it turns out, Scott doesn't sleep on Isaac's stomach when he lies on the couch, and he doesn't lick him when he wants attention the way Isaac imagined he would. Instead, the kitten sleeps at the junction of his shoulder and his neck, curled into a fluffy, purring ball right near his ear, staying there for hours while Isaac reads or watches TV, and when he wants attention or food he stands and walks directly across Isaac's chest or face, little paws pressing into him with all the force a less-than-one-pound kitten can muster.
It also turns out that Derek is as susceptible to the charms of teensy animals as Isaac is. Isaac brings Scott home, tensing for a fight when he sees Derek already there; for a moment it looks like Derek is about to command that Isaac turn around and leave, but then the kitten yawns and his face softens just a little. "His name is Scott," Isaac says. Derek's mouth twitches before he turns back to his book without saying a single word.
The next day Isaac comes home from school with Scott (the human) hot on his heels only to find Derek in the kitchen, rummaging through cupboards with Scott (the kitten) following him doggedly around the room. Isaac smiles, ducking his head to laugh just a little, glancing up to look between the two slightly perturbed men and the tiny fluff ball of a kitten. He might not have much, but sometimes what he does have is perfect.