Not really so sure about allowing a player character to be a half demon.
...Remember when I said, "You're only allowed to play another race with my permission?" Well, I'm denying you permission. Perhaps if you were to play as a more light-hearted devil, maybe, but I wouldn't allow something as dark as a tiefling to be a player character.
Aww. I even changed all of the faults so they would comply with your rules...
Do I really have to redo everything? I mean,
these two tropes technically apply to her. She's just a character with a dark past, she's not necessarily evil herself. She's just paranoid and has PTSD of sorts.