Billy Kaplan and His Glass Heart

(Everyone is 18+)
Billy Kaplan has always lived as the odd person out, but that only intensified when he found out he was adopted. Billy adored his parents, though sometimes he thought they didn't get him. He has powers, and no one knows where he is from; they are even scared of him at times, and it only makes him sad when he realizes that.

At the end of his rope, after being severely bullied for years without interference, he decides to recite a strength spell, even though he has done it countless times before. What happened differently this time? He went to an actual witch's house and used her alter ego, but where it went long is that Agatha pitied him enough to amplify his spell. All goes wrong when an 8-foot demon appears and possesses Billy.

When Billy realizes he is too far ahead of his capabilities, it is too late. He runs to the Avengers tower for help, and in return, he gets friends-a coven of his own. He even gets a couple of heroes wanting to jump in his bed. Most surprisingly, he finds Wanda Maximoff and Vision, who seem to know exactly who he is even though he thinks they have never met.