Check and check. So when was the first time? (Maybe I'm just being very blond) The second time something happens which keeps them from going back. I think, because he hasn't been around his place of birth very often, he doesn't find it strange that he was raised by a demon. He doesn't know better, I assume.
And yes, he'll have his own personality. But I'll let him take over a few things from his parental figure, the demon. I'll do something nice with all this :P Compared to normal human being he'll be a bit freakish in his own way. I really can't wait to see the progress in their relationship. I think this'll be a really interesting RP
Alright, so what else?