Class 1-A Radiates Chaos

BakuDeku:The Origin Story

Bakugou Mitsuki and Midoriya Inko had been friends since they were little. They were always attached at the hip despite them being a bit of an odd pair. They at one point had decided that they were going to get married, but that plan changed when they both met their husbands and decided to modify their plans to living in the same neighborhood and having kids who could be best friends as well. They were absolutely ecstatic the day they realized they were both pregnant around the same time.

~
About 9 months later a frantic and very pregnant Inko was driving a very vulgar Mitsuki to the hospital after her water broke while they were having tea. Mitsuki was currently swearing at a panicked Masaru to "hurry his ass to the hospital so she could get this fucking baby out".

That day Katsuki Bakugou was born.

~
Around 3 months later a frantic and very not pregnant Mitsuki was driving a hysteric Inko to the hospital after her water broke when they were playing with baby Katsuki. Inko had come over because Mitsuki was upset that Katsuki wouldn't smile like most babies do at his age and would make the baby equivalent of a scowl rather than smile. Instead of getting Katsuki to smile they got a screaming Inko while Izuku decided it was showtime.

After hours of labor, Izuku Midoriya was born and Mitsuki called her husband (Hisashi having left Inko) to bring Katsuki so they could meet.

Mitsuki sobbed when Katsuki grabbed Izuku's finger and smiled.

~
It was months later now and Katsuki was 9 months and little Izuku 6 months. Mitsuki and Inko were overjoyed to see that their boys were best friends like they always wanted. Izuku was honestly the happiest baby Mitsuki had ever met, he smiled like a little bundle of sunshine, while her equally adorable baby preferred small little smirks (unless Izuku was there then he was smiling up a storm).

At this age, both Katsuki and Izuku had started to learn to babble and crawl. Izuku was proving to be a fast learner and seemed to try to learn off of Katsuki. They would sit in their playpen babbling for hours with their parents occasionally coming over to try to get them to say, mama or papa, so color them surprised when neither of their first words was 'mama' or 'papa'.

Mitsuki had been babysitting Izuku for the day when they both started talking. Inko had come over to pick Izuku up and the moment she grabbed Izuku, Katsuki started screaming and crying at the top of his lungs. It honestly scared the hell out of Mitsuki seeing as Katsuki tended to just scream and not cry when he was upset. It must of scared Izuku too because he immediately started tearing up and squirmed in Inko's arms.

"Oh goodness. Izuku why don't you go say bye to Katsuki? He seems a bit upset," Inko set Izuku back in the pen (Mitsuki grabbed a camera), but Katsuki continued to cry. Izuku made the most determined face a baby could make and laid on his stomach and slowly but surely flailed his way about halfway across the pen until Katsuki joined in and crawled over to Izuku as if he'd always been able to crawl, but decided he wouldn't. What a little shit.

Izuku crawled up to the still crying Katsuki and slapped a hand onto his mouth to stop his crying. Izuku's scrunched up and he started babbling hysterically. Katsuki just stared, tears still rolling down his face. After a few minutes of babbling, Izuku let out a giant smile and yelled out "KACCHAN", then leaned forward and kissed Katsuki's cheek. (Or at least it looked like a kiss, he more or less slapped his mouth on Katsuki's face).

Inko and Mitsuki stared in utter shock, Katsuki also stared before smiling happily and babbling too. As if this moment already wasn't too much for their parent's hearts, Katsuki yelled out "IZU!" then hugged a giggling Izuku.

'Mama' and 'Papa' weren't said for another week or two. This interaction was the reason why nobody was surprised that the first time they walked had been together when they waddled to one another and fell down while hugging (completely ignoring their parents who were waiting for them to walk over to them).