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Izuku had rescued his cat Momo from the streets when she was only a few days old. Her tiny body had been filthy, patches of sleek black fur missing in ugly bald spots. She hadn’t opened her eyes yet; the only sound she made was the faintest, most proper little “mrrp” of protest when he lifted her from the rain-soaked cardboard box abandoned behind the agency building.
The vet had been brutally honest. “She's too weak. Round-the-clock care or nothing. Most people would just… let nature take its course.”
Izuku had clutched the kitten to his chest, green eyes blazing with that same stubborn hero spark everyone teased him for. “I’m not most people. And she will survive.”
Bottle-feeding every two hours, stimulating her with a warm cloth after each feed, measuring medicine with a tiny syringe at exact intervals—it was a nightmare of sleep deprivation and panic. All Might had simply boomed a laugh and said, “As long as young Midoriya’s reports stay One For All level, the kitten stays!”
He lived on internet tutorials during those first brutal weeks—“How to hand-raise a neonate kitten,” “Proper litter training for rescues,” “Enrichment for traumatized cats.” Todoroki left a heated cat bed on his doorstep without a word. Kirishima dropped by constantly, fists pumping, “She’s gonna be so manly when she grows up, bro!”
Momo improved like a proper lady should. When her intelligent gray eyes finally opened—after Izuku’s own were bloodshot from exhaustion—it felt like a quiet victory. The first time she took elegant, wobbly steps across his desk, she paused to delicately nose at a hero analysis notebook before bumping into a pen. Izuku cheered softly so as not to startle her refined sensibilities. Her fur grew back thick, lustrous, and perfectly black, glossy as midnight silk. Izuku tied a small crimson ribbon around her neck like a noble crest. She’d groom herself with meticulous precision, never a hair out of place.
She was the epitome of propriety: slept curled against his side with perfect posture (though she occasionally deigned to rest one paw on his face like a queen claiming her throne), greeted him at the door with a single dignified headbutt, and watched him cook from her designated cushion, tail curled neatly around her paws. She used her scratching post exclusively, never once missing the litter box, and would sit atop his hero textbooks as if personally overseeing his study sessions. Izuku would have done anything—fought any villain, rewritten any law—to protect his perfect princess.
That was why, when he spotted the enormous blond cat on his balcony one quiet afternoon, Izuku froze mid-step with a glass of water in hand.
The intruder was a massive ball of spiky blond fur that looked like it had been styled by a hurricane—long, fluffy, and somehow still managing to stick out in every direction. Crimson eyes locked onto Momo, who was napping in her sunbeam with flawless composure. The blond cat’s tail lashed violently side to side, and its mouth was pulled into what could only be described as a feral, toothy grin. Momo didn’t even twitch an ear, but Izuku’s protective instincts went nuclear.
He quietly shut the balcony door and drew the curtains. There were other pet owners in the complex, sure, but he’d never really interacted with them. If that cat was male… trouble. Big explosive trouble.
By the time he peeked again, the menace had vanished.
😼🐾😼
Ochaco Uraraka worked in the same support department, just a different section. They shared lunch breaks sometimes, and Izuku tried (and failed) not to stare—she was so warm, so bright, and her cheeks felt the squishiest thing in the world. To calm his racing heart, he always ended up scrolling through photos of Momo.
“Wow, she’s gorgeous!”
Izuku nearly dropped his phone into his curry. Ochaco plopped down beside him on the bench, letting a piece of rice float lazily before catching it with a grin.
“H-huh? Oh! Y-yeah, that’s Momo. My cat.”
“Super elegant! What breed?”
“Um, normal? She was a stray.”
“Adorable!” Ochaco pulled out her phone. “Mine’s a total chaos machine. Long-haired exotic shorthair or whatever the breeder called him.” She showed him the lockscreen: a massive blond cat with wild crimson eyes, spiky fur, and the most arrogant, explosive little grin imaginable.
Izuku blinked hard. That looked terrifyingly familiar…
“He’s… very… expressive,” Izuku managed, voice cracking.
Ochaco laughed, bright and bubbly. “Yeah, he’s a little bastard. Full name’s Katsuki Bakugou Murder God Dynamite, but I just call him Katsuki ’cause saying the whole thing every time he explodes is like saying oh my god every other minute.” She scrolled to another photo—the same cat drenched, fur plastered flat, looking skinny and murderously offended. “See? All bark, no actual fat. Just fluff and attitude.”
😼🐾😼
Katsuki returned the day Izuku accidentally left the balcony window cracked while dashing to the store for more premium kibble (Momo only accepted the organic brand that came in the elegant silver pouch). The second Izuku stepped inside, chaos erupted—crashing sounds, Momo’s refined but furious hissing from the living room.
“Momo?!”
His perfect princess was perched atop her cat tree like a queen on her throne, back arched with dignified outrage, every glossy black hair standing on end. Katsuki—fluffy blond tail lashing like a predator—was playfully (and aggressively) batting at her face with one oversized paw, that same feral grin plastered across his muzzle.
Izuku saw red. “Hey—!”
Katsuki tried to bolt in a white blur the instant he sensed the incoming human storm, but Izuku’s hero reflexes were faster. He scooped the cat up by the scruff. Katsuki yowled like a tiny explosion—“MEEOOOOWWW!”—twisting and kicking with all four paws, claws sheathed just enough to be annoying rather than deadly. Momo descended with elegant poise and rubbed once against Izuku’s leg, purring softly as if to say, “Well handled, human.”
Door-to-door with a violently struggling ball of blond fury was torture. Katsuki kept trying to claw free, yowling threats the entire time. Momo trailed behind like a proper escort, meowing delicate complaints. At the tenth apartment, Ochaco opened the door in comfy shorts and an oversized hoodie, hair slightly mussed, looking unfairly cute and half-asleep.
“Oh, that’s mine.” She plucked Katsuki from Izuku’s arms effortlessly, ignoring the cat’s indignant “TCH!” of a meow. “What the hell did you do now, little bastard?”
Katsuki stuck his tongue out and grinned wider, tail still lashing. Momo hissed once—perfectly timed, perfectly polite—from behind Izuku’s leg.
“Awww, is that Momo? She’s even prettier up close!” Ochaco crouched and offered a hand with zero hesitation. Momo eyed her for a long, dignified moment… then allowed a single ear scratch, purring like a refined engine.
Izuku scooped his cat up quickly, face burning. “S-sorry, he snuck in and… bothered her. She’s very particular about personal space.”
Ochaco grinned lazily, still holding the wriggling blond menace. “No worries. I’ll keep a better eye on this explosive gremlin. Promise.”
The next morning, Izuku woke to the sight of Katsuki sitting smugly in Mom’s bed, tail thumping like a victory drum. Ochaco showed up again in sleep clothes to retrieve him, and Izuku had to stare very hard at the ceiling so she wouldn’t notice how red he was.
It kept happening. Katsuki found new, increasingly creative ways inside—once through the vents, once by somehow scaling the building like a tiny villain—yowling demands the whole time. Momo would respond with proper outrage: a single precise swat to the nose, a haughty hiss, then an elegant retreat to her tower. But Katsuki was unbothered, always bouncing back with that explosive grin, tail wagging like a dog in a cat suit, kneading her favorite blanket aggressively as if claiming territory. He would yowl challenges at the vacuum, then immediately flop over for belly rubs the second he thought no one was looking—pure tsundere cat energy.
Izuku’s stress levels skyrocketed. The adoption agency was taking forever, Momo’s refined routine was being disrupted, and Ochaco kept coming over with that bright smile and those big brown eyes that made his heart do full One For All flips.
He still didn’t understand why Katsuki kept returning. Momo clearly found him deliquent—she slapped his face with perfect form, bit his ear when he got too close, chased him in dignified circles. Yet Katsuki never backed down, always returning with louder yowls and that stupid, defiant grin, secretly purring like an engine when Momo finally tolerated a single lick to her cheek.
One morning Izuku swore he saw Momo give Katsuki a very proper kiss on the forehead before delivering two precise paw-slaps. He blamed sleep deprivation.
Then one evening he came home to find both cats curled on the couch: Momo on her back in the most unladylike sprawl she had ever allowed herself, Katsuki kneading her stomach with surprisingly gentle paws while both purred in perfect, rumbling harmony.
Izuku’s scream could have leveled a building.
Ochaco arrived two minutes later, laughing so hard she had to float herself upright, wiping tears from her eyes while Izuku stood frozen, clutching a very confused Katsuki.
“He—he got my cat pregnant! Why are you laughing?!”
That only made her laugh harder. She gently took Katsuki back, the blond cat still grinning like he’d won a war.
“They weren’t doing that, Izuku-san. They were just… showing affection.” She looked at him with soft, teasing eyes. “You know… affection? Like, the kind where two people—or cats—stop pretending and just… let it happen.”
It took his brain three full seconds to catch up. His face went nuclear. Hours later, Izuku was holding a sleepy, flushed Ochaco against his chest, heart racing, when his phone buzzed—the adoption email had finally come through. Approved.
😼🐾😼
Izuku finally brought Eri home.
She had been waiting for this moment for weeks—ever since the paperwork started moving and Izuku had shown her endless photos of Momo on his phone. The little girl’s eyes sparkled every single time. “She’s so pretty, Oh Momo-chan I can’t wait to meet you” Eri had whispered, clutching the phone tightly.
Now, with the official adoption papers tucked safely in his bag and Ochaco walking beside him with a bright, supportive smile, Izuku felt like his heart might burst from happiness. Eri bounced on her toes the entire way up the stairs, clutching his hand tightly.
As soon as they stepped inside the apartment, Eri kicked off her shoes and called out in her soft, excited voice, “Momo-chan! I’m here! I finally get to meet you!”
Izuku smiled so wide his cheeks hurt. He was just about to call for Momo when two delighted little voices—one high and sweet, one dramatically loud—echoed from the living room.
“There’s a cat sitting on Momo!” Eri’s eyes widened. “Deku-nii! He won’t get off her!”
Izuku dropped his keys with a loud clatter. His face drained of color as he rushed into the living room, Ochaco right behind him, already biting her lip to hold back laughter.
“They’re making kitties, Eri-chan.”
The girl gasped in pure delight “Kitties?!”
“Yep,” Ochaco patted Izuku’s arm, eyes sparkling as she glanced at the two cats still purring shamelessly in the background “Looks like you signed up for a bigger fluffy family too.”
Katsuki gave one last delicate lick to Momo’s ear and yowled softly in victory, tail thumping.
And for once, Izuku didn’t scream. He just smiled, pulled Ochaco a little closer, patting Eri’s head softly, and let the chaos feel exactly right.