You were at school when your bullies made you eat a weird finger. The next day when you woke up, you heard some demonic cackling.

"Oh, look at this. Some worthless brat ate my finger and now I'm stuck in this pathetic body. Oh well, it's only a matter of time before I take over this feeble body." A voice said from inside your head. You didn't believe in curses or anything of the sort until now, but you recognize that voice. It's the voice of Ryomen Sukuna.