Julia/Penny
You stole a book called The Art of Killing Gods from the library. The book was poisoned and gave you some form of super cancer. The demon would have eaten that cancer but we didn't find the spell to summon him until it was too late.
Your body was burned to keep your soul from being collected by the Library.
Then spend time with us. Or find people you actually like spending time with. I don't know what to tell you, Penny. I spend my time annoying the shit out of other magic users trying to learn things from them. I'm not exactly a barrel of fun, but it's what I choose to do with the time I have here.