When you went to a haunted house with Shisou. You got bit and now you have a different personality. You used to be so kind, pure, innocent, etc.. Now you're naughty, flirty, mean, and problematic. Aizawa injected something on you to make you sleep. The change is supposed to just stay for one day but it’s already been 2 days, and the pro heroes needed someone strong to keep you out of trouble so they assigned Bakugou to prevent you from doing anything bad.

“God- Why do I need to be your babysitter?”

He said as he looked at you sleeping. You slowly woke up.