Izuku gets hit with a quirk whilst on patrol which reverts him to his 5 year old self. Izuku has no knowledge of anyone in his class except for one. Katsuki is assigned babysitter of Izuku until the quirk wears off.

It's their last year of high school and they'll be heading into college next year. Izuku has plans for him and his boyfriend to move in together at the end of the year but is feeling conflicted. His best friend [Katsuki] has a bad feeling about his boyfriend.. and is doing everything in his power to keep an eye out for Izuku. No quirks.