I'd like to know why the slave maiden is turned on and satisfied by the loaning to the buddies. If, as the reader, I ask 'why would she react that way' and the author writes the character with the depth to explain that to me, now that's a good story. In the OP's example, I would want to know why the woman tolerates being dressed like a slut 24/7. If it's not plausible, I'll put the book down. One book (non-erotic) was so bad I ripped the cover off and threw it away in an airport garbage can. That was brutal, 5 hours on a plane and only the worst book I've ever read for company. In another book I read, a good book, a teenage girl was captured and sold into slavery. No one laid a hand on her and she was taught technical skills because a technician was brought a much higher price than a sex slave. I'm sorry, but she would have been assaulted to pieces then taught technical skills. That evasion was an eye-roller. It would have been far more plausible if the author had mentioned that the girl's time in the slave facility was hell and that she was dealing with issues, and used that as a motivator instead of the you-destroyed-my-space-colony-now-prepare-to-die trope.