Geeky girl gets seduced by a demon who escaped hell and is hiding as a human on earth. The Demon is a sort of Hellboy-type of personality who for his own reasons is tired of being a demon and wants to try and be human for a while (sort of like a vacation) and falls for this geeky-type of girl. The girl begins to suspect that he might be a demon and tension mounts. The plot can go anywhere from there. I imagine really rough sex for this, but I am open to desires or suggestions.
Pleas PM me if interested.