ReedPipes
You summon a demon when you're young, you treated the demon nicely and gave them part of your lunch. You're all grown up now and just died, except… You aren't. At least you don't think so. You just got transported to a school for all the magic people when they die. But you aren't special, you're just a person who died in a car accident. Then, you get roomed with the devil's kid, the one you gave your lunch to when you were three and they utter eleven words. "I told my dad you were nice so he saved you!"