So, the first character is evil beyond sanity. She's the kind of masochist that should not get access to D&D-like regeneration but has it. If people around her do not give her what she wants, she threatens them. The idea is wonderfully executed, but giving here what she wants would be tantampount to torture, and torture is an evil act even if the other character likes it.
So my only option would be to turn my character evil (and I'd benefit a lot if my character became disgustingly evil as well, mechanically speaking), but this means I'd have to change my behavior with all other characters …