Bakudeku/Dekubaku Oneshots AU

Age Regression

A knock at the door pulls Katsuki out of his train of thought, his body instinctively shooting up to go open the door.

Deku was at work, so he was all alone in their apartment waiting for him to return. He glances at the clock on the living room wall, still about two hours before Deku should be coming home.

Even so, Deku stopped knocking to come in long ago. Katsuki had to practically beg him to knock it off and just come in; it was his home, too, after all.

Katsuki reaches the door, hand on the knob as he pulls it open. He’s met with an exhausted looking Kirishima, his face covered in worry. In his arms is Deku, he’s holding him bridal style.

Before Katsuki could even open his mouth, Kiri quickly explains what happened.

“Bakubro, you won’t fucking believe it. He got hit with one of those age-regressing quirks. He’s still him, just.. younger? He caught the guy but he managed to hit Deku as he was being restrained.” He rambles, eyes wide.

Katsuki raises an eyebrow, studying Deku’s form in Kiri’s arms. He definitely still looks like himself, but his eyes are somehow wider and more.. childlike. He’s got the goofiest smile on his face as they lock eyes.

“Kacchan!” Izuku squeals, reaching out and making grabby hands at the blond.

“He wouldn’t stop asking for you the whole way here. He was—and is—so excited to see you, bro,” Kiri says, his expression softening as he looks down at Deku.

Katsuki reaches for him, his arms wrapping around his waist as Izuku latches himself to his Kacchan—arms around his neck and legs wrapped around his waist—koala style.

Kiri lets out a low chuckle before giving Katsuki a quick wave. “Gotta get back, he’s allowed to stay home until the effects wear off. Good luck!”

And with that, he disappears down the corridor and Katsuki shuts the door.

Izuku nuzzles his head against Katsuki’s shoulder, humming quietly as his body relaxes. Katsuki walks them over to the couch, attempting to separate Deku from himself but failing miserably.

The brat has the strongest grip in fucking Japan.

He huffs, sitting down on the couch with Izuku in his lap. Izuku hums again, his body going limp again against his Kacchan.

Izuku was probably content with the silence, but Katsuki was beginning to stir.

“So, uh, how was your day, ner-Izuku?” He says, catching himself in his speech.

Izuku’s head pulls back to face Katsuki, their faces mere inches apart. There’s a huge smile on Izuku’s face as he spoke.

“It was soooo good, Kacchan! I had such a yummy lunch that I just know you made for me because it tasted like Kacchan’s cooking!” He rambles.

“Then I caught lots of bad guys, like a super strong hero! I protected everyone today! It was awesome!” He boasts. Quickly, though, his smile drops into a small pout.

“But then a bad guy got me, and now I feel so.. little. I feel small and weak, I just want to snuggle and be held and taken care of—like a stupid baby!” He huffs, his arms breaking free around Katsuki’s neck to cross over his chest.

Katsuki chuckles, watching the sudden range of motions that Izuku hurdles through in such a short time.

“Don’t laugh! Not funny! Kacchan is such a meanie,” he whines, his bottom lip sticking out in the most adorable pout Katsuki had ever seen.

“Okay, okay. My bad,” he says, his voice way softer than usual. “What can I do to help?”

Izuku eyes Katsuki’s face, his furrowed eyebrows adding even more adorableness to his pouty face. “I want to snuggle with Kacchan. And watch a movie. And—and I want Kacchan to kiss my forehead.”

He huffs, that last one sounding more like a question than a demand. Katsuki smiles a small, soft genuine smile.

“Got it,” he says, his fingers carding through luscious green curls. “Is this snuggle party happening here on the couch or in our room?”

Izuku’s eyes practically shine with excitement. “Kacchan and Izu’s room! Kacchan and Izu’s room!” He chants, giggling in between.

Katsuki nods, a small laugh escaping at just how cute Izuku was. “You got it, Izu.”

He tightens his arms around Izuku’s waist as he pushes them up off the couch, carrying his little green koala to the kitchen so he can grab the movie snacks.

He grabs all of Izuku’s favorites, all of which also happen to be Katsuki’s favorites, as well. Snacks in one hand and a latched on Izuku in the other, he makes their way down the hall to their room.

He sets Izuku down on the bed, a whine immediately erupting from Izuku as Katsuki walked to the dresser, pulling out one of his comfy t-shirts for Deku to wear.

He turns back around, walking back over to a pouty Izuku. “Sorry, Izu, but you’re still in your hero costume. Gotta get you in some comfy clothes, right?” He says, holding up a Kacchan sized t-shirt.

Izuku squeals, his pout immediately dissipating at the sight of the fabric. “Really? A comfy Kacchan shirt?”

Katsuki nods, reaching forward to help Izuku undress. He begins to unzip his zipper, and Izuku’s eyes widen as a bright red blush spreads over his cheeks.

“N-no no! It’s okay, Kacchan—I’m a big boy, I can do it myself!” He insists, pushing Kacchan’s hands away.

Katsuki curses himself for not realizing that he could cross some invisible lines, raising his hands up in the air in defeat. “Okay, got it. Do you want me to go away while you change?”

Izuku shakes his head. “No! I’ll just change over there, just don’t look, okay?”

Katsuki nods his head, sitting himself on their bed as Izuku climbs off the bed and walks over to the dresser, back turned to Katsuki.

He unzips his costume, slipping it down his shoulders and arms and letting it plop onto the floor before he steps out of it. Katsuki does everything he can to not look until a partially clothed Izuku is in his line of sight.

Katsuki’s t-shirt draped over Izuku’s petite but muscular build, the bottom of the shirt ending at the middle of his thighs.

“All done!” Izuku squealed, running and jumping onto the bed. He crawled up the bed to his Kacchan, stopping to sit on his knees in front of him.

Katsuki smiles, a hand reaching up to pet his green locks. “You look absolutely dashing, Izu.” He says softly, leaning forward as he plants a gentle kiss on his forehead.

Izuku practically explodes, his cheeks pink and his eyes squinty as he smiles. Katsuki pulls him towards him, turning him around so Katsuki is behind him. He shifts them, laying them down on their left sides so they can face the TV.

Izuku nuzzles his cheek against Kacchan’s bicep, resting his head on it as if it’s a pillow. Katsuki turns the TV on, allowing Izuku to pick the movie. To no surprise, another All Might documentary.

As they settle in for their movie night, Katsuki leans down, a gentle kiss grazing the crown of Izuku’s head as he inhales and just revels in the scent of his soft curls. He smelled like home.

Izuku giggles as he plants a small, soft kiss on Kacchan’s bicep. “Kacchan’s the best! He’s shoooo comfy!”

Katsuki chuckled, wrapping his free arm around Izuku’s waist. “I think Izu’s the best, such a kind boy! Such a strong hero, like All Might!”

Izuku practically screams at the comparison, his excitement overflowing. “REALLY? You think, Kacchan?!”

Katsuki nods, a simple ‘yep’ leaving his lips.

And he truly thought so. Izuku was an amazing hero, an amazing friend—an amazing partner. Katsuki’s more than happy to spend the rest of his life taking care of the brat..

Even if he was hit with weird quirks here and there.

END