It might be possible for some to root for the new guy, or in an erotica sense get pleasure through him- I kind of can, but only where the groups of women don't overlap. I bet this hits more if you're more a switch or at least get off on the disempowerment
Yeah, that's the main thing for me. Especially where the main character is so blank to the point that we're supposed to project into them (which I wish there was less of, tbh, and that less of the protagonists were "generic white dude with brown hair #37"). *Part* of why I enjoy mind control is the power fantasy aspect of it, so yeah, flipping it around defeats the point. For people who put themselves into the controlee role, I could see how it would be enticing - "I'm so desirable *multiple* people want to control me!" - but that's not me, really.