Bkg gets de-aged to around a year old (don't ask how). Aizawa calls mitsuki so she can take him home, but she just laughs, says "good luck" and hangs up.

Aizawa likes kids well enough but this one screams like a fucking banshee so he pawns little bkg off to his classmates lol

Except bkg is clearly aware that these people are Not Family, so he squirms and complains until iida points out the only person he probably knows is deku

Deku: i, uh, i don't think he's going to be happy about that

Bkg, attempting to rip Kiri's hair off his skull: AIIYEEEEEEEE

Deku fully expects to be bitten but bkg just stares at him for a long time before evidently deciding that deku is Acceptable

Goes "abababa" and smacks deku on the mouth with his chubby baby hand

Deku is bewildered but at least bkg isn't trying to kill him so ok this is fine

Bkg despises the rest of his classmates and also refuses to walk because he's a bastard. deku gets bullied into carrying him around everywhere like a wriggly stuffed animal

Bkg's not even that fond of him, he just likes being high up off the ground lol

Deku, on the phone: mom. Mom i am so sorry. Kacchan keeps making me carry him and my arms hurt. I was such a clingy baby. I can't believe you had to go through this

Inko, lifting the couch off the ground with one hand to vacuum underneath: oh, honey, you get used to it

The boys take turns on diaper duty. Iida makes a roster. Most of them are completely useless at it and bkg screams the dorm down until tsuyu elbows kaminari aside and show them how it's done. They uninamously agree that bkg will never hear of this, ever

The girls fight to take turns feeding him until they figure out he's usually more interested in playing and it's impossible to coax him into eating his mushed peas. Ojirou eventually discovers he can distract bkg with his tail and shove food into his mouth when he's not looking

Bkg sleeps in his own room with a walkie talkie (makeshift baby monitor). He thankfully doesn't cry at night but he DOES wake up at 5am on the dot and yell to be fed and changed. Poor deku is forced to fix his shitty sleeping habits purely because of this

Once he settles in bkg likes to stare intently at whatever enters his field of vision. It's hilarious watching him explore the common room bc he's fat and wobbly but is clearly trying very hard to walk lol

Kami: you stop that you little gremlin OW DON'T HIT ME

Deku: what's going on?

Kami: this jerk keeps trying to put milk in the bluray player!!

Bkg: ABABA BABOO

Deku: oh, kacchan, are you worried the player is hungry? They don't eat people food, they eat CDs. See?

Bkg: ?

Deku: here, hold it! Shiny, right?

Bkg:

Bkg, putting it in his mouth: bapapap

Hagakure manages to scoop him up once and bkg is mystified. Why is he floating. Why is this animate school uniform holding under the armpits like simba on pride rock. He obviously wants to yell but he's too confused to do much more than kick his little sausage legs and grunt

Unlike big!bkg he likes to be chatted with. He seems to understand pretty well and actually gets upset when they baby talk him too much haha

Ashido: kacchan! Who's a good baby! Who's a bouncy baby boy!

Bkg, indignant: aggobapoo!!

He's very grabby and will try to take whatever interests him. Tsuyu's hair. Jirou's earlobes. Iida's glasses. Ojiro's tail. Nothing is safe from his small kleptomaniac hands

He is terrified and fascinated by shouji. Also one time he points at tokoyami and just says "borb"

Uraraka: oh no why are you crying?

Deku, lying face-down in the floor: i showed kacchan my new all might figure and he put it in his mouth

Bkg: goobapibo

Deku: IT'S NOT A TOY IT WAS IN MINT CONDITION

Deku takes him to class in a baby carrier and bkg is a HUGE distraction so they just plop him at his desk

He fusses until they let him crawl around the teacher's desk instead

He eats aizawa's pens and drools on his paperwork but aizawa doesn't yell at him lol

He warms up to momo because she shows him her books and reads to him while he admires the pictures

For some reason he likes iida too. Probably because iida has no idea how to deal with babies and just talks to him like an adult i guess

Also bkg's like a cat and can tell who's uncomfortable around kids. He loves to harass tdrk by sitting in his lap and shouting at him

Poor tdrk is bewildered and can't push bkg off because he's afraid he'll break him or something. He's just so squishy. How r his fingers so small

Also why does bkg keep throwing baby food at him? Is this because tdrk wouldn't share his lasagne that one time? Deku's no help. Nobody understands bkg's behaviour so tdrk is doomed to be pelted with cheerios and suffer in heterochromatic silence

Bkg's other hobbies include crawling after kouda's rabbit and watching action movies. He'll sit on the floor with one of hagakure's plushies clutched to his chest, wide-eyed at the screen while jackie chan fights ten men bare-handed.

OF COURSE, says deku. Bkg loves heroes, quirks and combat. Obviously there's a mad scramble to to show off for him lmao. Aoyama's shiny navel is well-received. Kirishima's unbreakable is a hit. Uraraka floats bkg up to the ceiling and he squeals so loud her ears hurt

Iida puts a stop to it after ashido melts a big hole in the carpet. At least bkg is slightly warmer towards them. Once they catch him trying to imitate dark shadow and tokoyami actually giggles. Kaminari has this on video.

At one point all might musters up the energy to go into muscle-mode and bkg's starstruck. He's teeny tiny in AM's hands but reaches up to reverently pap him on the face

He insists on being held until he falls asleep. AM is delighted. It's absolutely worth coughing up blood for

They get used to a baby hanging around the dorms so by day four it's more fun than stressful. Bkg's honestly adorable even if he is a little demon and momo has the truly inspired idea to make him silly costumes to take photos in.

Tiny sailor. Tiny lobster. Tiny all might. Deku sends all of them to mitsuki and inko. He also takes the opportunity to cuddle bkg as often as humanly possible. Bkg still isn't all that impressed with him but he tolerates being held so deku takes what he can get hahaha

It lasts a week. Bkg comes out one morning, all grown up again, demanding to know what happened and why everyone looks like someone died.

Kaminari, moping on the couch: I've never wanted a son so badly

Bkg: what the fuck?

Predictably, bkg tries to hunt down and destroy all evidence but he does also make everyone dinner to say thanks for babysitting him

(dw the photos are fine. Deku backed them up to like 17 servers)

Deku's still sad and misses baby bkg, mainly because he's not bkg's favourite anymore. But one night he hears crackling from the walkie talkie he forgot about

Bkg: come in, nerdling. It's me

Deku: kacchan? What's the matter?

There's silence for a second. Deku thinks bkg hung up, but then

Bkg: i heard you did even more than the others. So, uh, you know. Thanks or whatever. For looking out for me even though i must have been a pain in the ass

Deku's obviously delighted by this. They end up chatting late into the night until bkg falls asleep

After that it becomes a habit for them to use their silly walkie talkies instead of their phones. Bkg still calls them baby monitors, which makes deku laugh.

They keep it a secret from others. it's all very cute and sweet and they eventually get closer, maybe even develop a mutual crush. Everything's perfect and lovely

Until deku gets de-aged the next month

And the first thing he does is throw up on bkg's shirt

Ok lol this was all very silly and self indulgent SORRY NOT SORRY KEK https://ko-fi.com/E1E2OGQQ 

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