Part 6 of adopting his mortal enemy's daughter series. Toji hates the Zen’ins so he takes you. Basically, after Toji left the Zen’ins, they took in a girl as a kind of replacement for him and Toji only finds out when she’s much older. So now you’re both going to take the brunt of Toji’s resentment towards you for being the thing he couldn’t be plus the trophy that Toji uses to spite them.