When I was younger I wrote several pieces of lesbian BDSM erotica, not because I was a lesbian but because I appreciated that the two people exchanging power were not saddled with the burden of an assumption of male dominance. They didn’t have to subvert the paradigm, and they didn’t have to justify following it, either. I struggled particularly with fiction where the man was on top, because it seemed to me that he was already in a position of some advantage in our society, and how dare he exploit it to gain even more dominance in a power exchange, which didn’t stop me from finding those books hot. Now, that concern seems, if not precisely silly, at least not important to me personally.
A year or so ago I read a book in which a psychologist uses information from counseling sessions to “help” his patient by becoming, along with his brother, her dom. It was, again, pretty hot, but not so hot that I could shake the little voice inside me that kept saying “but that’s totally wrong.” I enjoyed the book anyway, but I would have enjoyed it more if the setup had been different.
People in positions of power can be hot fantasy figures. Doctors. Policemen with handcuffs. Bosses. Psychologists. Pirates. Teachers. No one can blame the submissive heroine for wanting the one she wants, but at the same time it may be crossing all sorts of ethical lines for the dominant hero to actually give it to her.
When writing Secretary for Two my setup involved an executive assistant and her boss, and her bosses’ brother. Clearly, she’s starting out in a position of imbalance, and her ability to negotiate is a bit challenged. Clearly no good boss is going to make someone submit when he has the power to make them lose their job. However, I think I came up with a reasonable solution to that issue -- I’ll have to see what the readers think, but I think people will finish the book liking everyone.
In any case, fiction is a kind of fantasy. Maybe we don’t want heroes to obey the rules, even when it comes to ethics. That’s not my take, but I don’t want fictional doms to be perfect either, and I certainly read books where the hero ruthlessly exploits his societal advantages and enjoy them. But I try to describe basically safe or at least risk-aware BDSM practices in my books, and ethical characters are part of that.