(A/N): Alrighty the premise of this next "side effect" drabble is of Bakugou and Midoriya getting turned into animals! Hope you enjoy!

Katsuki was so going to kill someone. One minute he was readying himself for school and in a puff of smoke he was much smaller and buried in his own clothes. As soon as he crawled out of the pile of cloth Katsuki made sure to check himself over. He wasn't just shrunken down, no, he wasn't even human anymore.

Oh hell no! He hissed, very literally hissed. He was a cat. A cute little ball of puffed up fur cat. He had no idea what he was to do. But then he remembered something from the day before. He wasn't the only person that had helped deal with a random villain the other day.

Deku…fuck. Katsuki huffed as he realized that the other boy could also be in this type of situation. He really did not want to deal with his "rival" but he still knew he had to do something about all this. Thankful that he had left his bedroom window open, Katsuki, though through a couple of stumbles, made his way up and out. As he wandered the sidewalk Katsuki sort of enjoyed this whole cat thing. For the most part he was getting ignored and he was very light on his feet. The world had all kinds of smells he never knew before and the whole cat-sight was an experience. The blond was making good time to U.A. and was proud of himself; tail flagged high at the fact. That was until something caught his eye and sudden urges came over him. Something small was quivering in some bushes. Katsuki ducked low and crept towards the bush. Claws slowly slipped out of Katsuki's paws and inside his head he was a tad conflicted. He didn't want to succumb to kitty desires, but this also felt so right. Just as Katsuki was to pounce the object of his fixation was suddenly scooped but by human hands.

"Oh no kitty, you aren't eating Mr. Bunny." Katsuki recognized the U.A. uniform, but he had no clue who it was he was looking at. Gravity-Defying purple hair and tired eyes looked right the catified-human along with a strong smell of coffee in the air. After deciding he didn't care about the person Katsuki looked to his previous prey. In the human's hands was a green-furred rabbit that was shaking like a leaf. Something seemed oddly familiar about the rabbit and it pissed Katsuki off.

"Now then what are you two doing out here?" The human tucked the rabbit under his arm and knelt down closer to Katsuki. With a free hand the human held it out the the feline. Katsuki hissed at the human. He wasn't some stray cat to get coddled!

"Angry little thing eh?" The human rolled his eyes and stood back on his feet. He then turned to the rabbit under his armpit. The rabbit made a pathetic squeak and shook just a little less. "Well at least this guy accepts a helping hand." The human turns his back to the cat and starts to leave.

Good fucking riddance. Guy had shittier hair than Kirishima. Katsuki sticks his little pink nose in the air and continues on his journey to inside the school. Glad that the hallways weren't crowded Katsuki made his way to class 1-A. Taking a peak inside he tried to spot Izuku.

"I haven't heard from Midoriya since yesterday. It's not like him to not come to class." It was good-ol' Half and Half that was talking.

"I hope he's okay. He was in that fight yesterday after all. Say Kirishima have you heard from Bakugou?" It was Ochako that was speaking this time.

"Nah, normally when I bug him with as many texts as I have he curses me out to leave him be." Eijirou shakes his head and pouts. Katsuki can feel his fur start to stand on end. Great now whenever he's back to normal he's going to have to deal with the red-head's whines and ridiculous emojis. However, as the others' words start to sink in Katsuki realizes something. He was turned into a cat, Deku was missing, and he and Deku both were involved in the attack the other day.

That fucking rabbit! A lightbulb goes off in Katsuki's head as the pieces all fit together. He needed to go find shitty hair 2.0. The little blond cat is soon skittering across the U.A. hall tiles as he goes to look for the purple-haired background character. When a recognizable coffee scent fills Katsuki's nose he knows just where to go. He ends up in the General Studies area of U.A. and Katsuki can't seem to find the words to describe the fact that he had to wander here. But to the most of the blond's surprise he didn't have to invade a classroom. Instead, in a Aizawa-like manner, Katsuki finds the human of his hunt dozing up against a vending machine.

What the fuck are you doing out here? Katsuki rumbles as he gets closer to the person. You should be in class shithead! An eye cracks open and a smile finds its way to the human's face.

"Hello again kitty-cat."

Where'd you put that rabbit-Deku?! Katsuki wants to speak but all that comes out of his mouth is mewls. The human only chuckles and goes to run a hand down Katsuki's back. Dammit that felt nice.

"This is no place for you. Come here." Before Katsuki could realize what was going on, he was up in the human's arms.

Let me go fucker! Katsuki yowls and sinks his teeth into the human's hand. But the human only laughs.

"What a wild thing you are…you remind me of a certain someone from the Sports Festival."

The sports festival? Wait a minute…You! Katsuki let's go of hand; he finally recalls who this person is. The brainwasher that almost pathetically whipped Deku's butt. What was his name again? Shin-something. Katsuki rumbles as he thinks.

"Say, can you promise me not to attack the bunny again? The two of you are going to have to share a space again for a little bit. Cause I doubt you want to be around here like you currently are." Shin-whatvever rambles as he heads to the dormitories that aren't too far from the school itself.

This little shit already rooms at the school? Katsuki looks up to Shin curiously. But it appears the human is no longer in a talking mood. He simply hums as he continues into the dormitory. Once into a room, of which Katsuki can only assume is Shin's own, he is finally let down. Feet back on the ground he trots away from Shin only to turn and glare at the person.

Where's Deku? He meows.

"Hungry? I don't really have anything cat-safe for you right now." Shin takes a hand and rubs at the back of his head.

No! I need to see if that stupid rabbit is Deku! Katsuki hisses.

"Geez, not one for taking apologizes?" Shin chuckles and walks by petting Katsuki as he goes. Rolling his eyes, or at least thinking he is, Katsuki wanders off to search for the green bunny. He comes across the fluffy bun quiet easily and has to jump a desk to come to him. The rabbit's eyes grow wide as he stares at the incoming predator.

Now then are you Deku or just some random fucking rabbit? Katsuki meows at the bun not sure if he can even understand him. The rabbit jumps and after spinning in confusion, hops off the desk and runs for it. Fuck you! Katsuki gives chase; which probably wasn't his best idea.

"You piece of shit." Katsuki is scooped up after he runs by Shin. "I said not to chase the fucking rabbit." Katsuki only gives the other a bored glare. By now the rabbit was huddled up in a corner heavily breathing.

Not my fault he won't stay still enough to talk to me! Katsuki huffs.

"I think you need a cat nap…I know I do." Shin sighed and despite the last part being whispered, Katsuki heard it perfectly fine. Shin heads to a bed and plops right down, making sure to let Katsuki free onto the mattress as he did so. Said yellow cat couldn't help but jump slightly as the mattress moves when Shin lays back onto the bed; evidently passed out.

Does this dumbass not sleep regularly? Katsuki can't believe that he's now caught this person asleep twice. Sighing to himself Katsuki curls up next to the human; there's not much he can do until the rabbit calms back down and honestly, a nap sounded nice. As he closes his eyes he can feel a hand sudden go across his flank.

"What a good kitty…" Deciding not to care for now, Katsuki let's the petting happen with no fuss on his end.

K…Kacchan? Katsuki perks up at the call of that horrid nickname of Deku's.

So you are indeed Deku. He huffs as he adjusts himself to spy the rabbit while staying curled in the bed.

You're being awfully nice to Shinso. Izuku hops a bit closer to the bed.

Is that his name? Katsuki shakes his head, Whatever, why the fuck did you keep running from me?

How was I supposed to know it was you? I thought you were going to eat me! Izuku actually makes some kind of noise as he perks his ears.

I should have if you're going to keep whining. Katsuki's ears pull back as he snarls.

Kacchan! Deku spins in a circle as he squeaks.

Guess now that I've found you we should go find Recovery Girl or something. Katsuki seems to sigh as he stands and stretches.

But how will we let her know it's us? Same can be said if we try to see if Mr. Aizawa can cancel this Quirk effect. Deku flops onto his side as he seems to be worn out.

Better than staying here and becoming this guy's pets. Katsuki claims as he comes down from the bed.

You didn't seem too adverse from the idea. Izuku comments and is quick to dodge a swipe from a fluffed up Katsuki.

Let's go. Katsuki sternly states and starts to head to the door. The two turned-animals carefully make their ways out of the dorm room and dormitory altogether. They go through a few verbal spites as they make it into the main U.A. building.

We are so lucky that we're wandering the halls when nobody is around. Izuku comments as he and Katsuki are almost to Recovery Girl's.

Don't count your blessing too soon. Idiot. Katsuki huffs in response.

"Oh what's this? Where'd you come from. That and a rabbit and cat so close together and not fighting?" Both Izuku and Katsuki turn around to see Principal Nedzu. The pair can only give their Principal a deer-in-the-headlights look.

What should we do Kacchan? Izuku asks with his ears flopping down.

How the fuck should I know? Katsuki returns with a hiss.

"Ah I thought you two looked familiar. Now Mr. Bakugou please try and control that language of yours." The Principal wags a finger at the cat and bunny.

Guess he can understand us. Izuku points out.

Obviously! Katsuki huffs. Principal Nedzu proceeds to grab the pair and walk them to Recovery Girl's. While doing so he makes a call for Mr. Aizawa to meet him there. Soon enough the two boys are back to their human selves (and put in some replacement uniforms one would add). The day is then treated as if the pair was sick at home for the school day and would be back into the normal swing of things the following day. Though when said day comes by, Katsuki makes a small detour on the way to class. He finds a sleepy purple-haired peer out on a bench by a training yard and leaves a thermos of coffee by his backpack.

"…Thanks, I guess." Katsuki quietly states as he leaves. But little did he know, Shinso wasn't completely asleep.

"I wonder what that was about…" Shinso grins as he takes a sip from the thermos the U.A. asshole has left him. "Damn that's good stuff. What a good little kitty." His snickers are thankfully heard by no one.