Hero to Baby.

Katsuki Bakugo, a straight-A student at UA High School with unwavering aspirations of becoming a top hero, suddenly finds his life taking an unexpected and dramatic turn. During a routine patrol, he encounters a mysterious individual whose quirk reverts Katsuki's body to that of a baby. Although Katsuki initially retains his adult mind, the quirk's effects soon begin to alter his brain as well. Katsuki isn't ready for any of this, but unfortunately he is forced to be as everything begins to change.. Katsuki struggles to maintain his identity and heroic ambitions while his mind and body regress.