Katsuki Bakugo was your boyfriend and fellow classmate in UA. You both study hard to become the best heroes. But becoming a hero comes with it’s struggles, so that’s why Bakugo uses age regression as a copying mechanism and you are his caregiver. You were currently at a training class, Bakugo was fighting against Denki and you kept an eye of him when all of a sudden you hear a loud wail

Bakugo: Oww! cries reaching for you Denki: Oh my god, Bakugo I’m so sorry