DEKU gets de-aged to around a year old (don't ask how). 

Aizawa video calls inko. She wants so badly to take izuku home but she's been sick for a few days and she's terrified of passing it to him. She makes aizawa promise to call and send photos EVERY DAY.

Obviously she demands he hand the phone over. Izuku lights up when he hears her voice and Inko BAWLS when she sees him because she forgot just how fucking beautiful he was. You thought teenaged deku was cute? As a baby he looks like an actual cherub.

Big shiny eyes, chubby pink cheeks, fluffy flyaway hair... He's genuinely irresistible. The only reason aizawa doesn't bring him home then and there is bc 1A threatens to riot. He (grudgingly) lets izuku stay in the dorms and there's an immediate clamour to hang out with him lol

Bkg obviously volunteers to do the caring (deku's HIS, after all) and yells at anyone who dares touch izuku without permission. He fully expects little deku to cry and cling to him like a koala so he's completely prepared to go guard dog (even after deku throws up on his shirt)

But deku doesn't even care who has him half the time and that makes bkg LIVID. How dare deku not have a favourite. How dare deku not mind uraraka scooping him up. How dare deku pap tdrk's face and play with iida's glasses. This is unacceptable, deku should only like BAKUGOU

(un)fortunately deku seems to recognise his friends on some level (or he just has no sense of stranger danger which.... Might be more likely actually). He'll crawl to whoever calls him and let himself be picked up and swung around without issue

Little deku is fearless and has no common sense but a lot of love in his curly head. He wants to be held constantly and tries to befriend everything. He's also EXTREMELY curious. It's a terrible combo because he'll crawl straight into danger if it's shiny and interesting

He tries to touch aoyama's lazer beam. He tries to touch mina's acid. He tries to touch hound dog which makes 1A fear for their lives but deku's so cute the guy lets it slide just this once. Deku chews on hound dog's ear and coos. Hound dog dares them, with his eyes, to comment

Unlike bb bkg it's very easy to get deku's attention!

Bkg, showing deku his hero gear: see, nerdling? I'M your favourite hero. Look how cool my mask is. Here, try it on

Deku, wearing bkg's mask which is entirely too big for him and is already slipping off his face: happapap!!

Bkg bullies momo into making a mini ground zero mask. Deku refuses to keep it on but does seem to enjoy chewing on it so bkg calls that a win. He doesn't need to ask for more stuff. Momo's already pulling out the outfits she made the last time. They take SO MANY photos.

Iida: are you sure it's safe to let him touch your costume like that?

Bkg: what's he gonna do, assume my identity lol

Deku, pulling the pin on one of bkg's grenades: nyoooo

1A has the absolute time of their lives until they figure out deku cries. A lot. JESUS CHRIST does he cry. At the toaster going off. At the blender. At koudas rabbit stepping on him. Half the time they're sure deku doesnt even know what he's crying about. He just thinks he should

Aizawa asks inko what to do about it. Just distract him, she says. The next time deku cries aizawa hands him one end of his scarf and tells him to go wild. Deku immediately stops crying and tangles himself up in it. Aizawa makes him a weird hammock to carry him around in class

All might, sidling into the dorm: so... I heard young midoriya's a baby now

Bkg: do NOT go muscle mode. You'll give yourself a hernia

All might: well then how else am i meant to impress him???

Bkg: just say hi or something like a normal person

All might: ugh alright

All might, taking a deep breath: YOUNG MIDOROYA, I AM HE- oh no he's crying

Bkg scolds all might for startling deku lol but the second he puts deku in AM's arms he stops crying

He just looks at him. Sniffling, red faced, teeny tiny in his hands

Plaintively goes "igubapoo" and puts his head on AM's chest

AM has to turn around to weep

Obviously the dorm gets streams of visitors who wanna get a look at minidoriya. Bkg guards him with the jealousy of a testy dragon. Insists on keeping the baby monitor (walkie talkie) in his room. Makes sure deku's fed and changed and entertained. He does a great job actually

It's also very funny to see bkg arguing with a baby. Deku won't eat his mushed peas so bkg lovingly threatens to toss him out the window

Bkg, bouncing deku on his knee, singing: go to sleep you little shit, I'll smother you with a pillow, why in gods name won't you fucking sleep

Kaminari, holding his phone: aww, look at mama bkg with his little boy

Kiri: aren't they just the sweetest. Bkg was born for this dont you think?

Sero: maternal instinct. The guy really has it all

Bkg, quietly because deku's asleep on his chest: i will cut your fucking throats

Kiri, holding deku with one arm and eating a sandwich with the other: bkg's just in the bathroom little buddy! He'll be right ba - ah, heck

Bkg: I'm done, hand him ove- why are you licking the baby's forehead

Kiri: dropped mayo on him sorry lol

Deku's very chatty and friendly!! And also kind. He likes to share his food and if you pretend to cry he'll give you his teddy lol. He loves to be talked to and mimics movements, so everyone's favourite thing is to dance with him cause he'll follow along hahaha

Bkg: stop hyping him up like that, asshole, he'll never get to sleep

Ura: don't swear in front of him, he's a baby!

Bkg: Deku, what's your name?

Deku: abooooblblb

Bkg: see. He doesn't know shit

Deku: shit :)

Anyway they're all sad to see him go when the quirk wears off. Deku has no idea what happened but is embarrassed. His mother also calls to cry at him because she missed it but he consoles her by sending bkg's file. It has 204659 photos and 2947 videos. Inko cries even harder

Deku, fifteen again, can't get to sleep. He lies in bed, the makeshift baby monitor on his nightstand, staring at the ceiling and trying to force himself unconscious. Sleep doesn't come. He reaches out and presses the button, saying very quiet "come in, kacchan"

Surprisingly bkg answers. He says it's because he was so used to checking up on deku.

Deku: thank you for taking care of me. The others said you did a lot

Bkg: yeah, don't worry about it. You did the same for me

They chat late into the night like they've been doing a lot recently, before this whole baby fiasco. Deku rolls over in bed and sighs.

Deku: i don't know why i can't sleep.

Bkg: that hasn't changed. You were like that as a kid too

Deku: how'd you handle it?

Bkg: i, uh.

Deku: hmm?

Bkg: i might have... Snuck you into my room and cuddled you a little

Deku: oh my god

Bkg: you're clingy, it's not my damned fault

Deku: that's adorable. You cuddled me to sleep? Every night?

Bkg: maybe i did. Seemed to help, anyway.

Deku: thank you, kacchan. I appreciate it.

Bkg: whatever.

Deku: kacchan?

Bkg: what?

Deku: i, uhm. I can't sleep right now.

Bkg:

Deku:

Bkg, sighing: I'll come over.

(By the way this is sort of a continuation of this thread, although you can read it as a standalone. The deku version was heavily requested on kofi.) https://twitter.com/supercrunched/status/1295733798286446592?s=19

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