Actually, I will say one thing. I haven't read the book, but it is obvious that some people seem to see something problematic with the ambiguity of consent to what seems violent and to some extent abusive sexual acts.
However, maybe people are missing the point of why some women seem to like the book. It is a work of fiction, not real life. A 'rape fantasy' of course is imagining a scenario where you are sexually assaulted without consent. If that is what they are into, I suppose they would want their fiction to be believable. What they perhaps wouldn't want is every scene to be qualified with obvious consent. That would be what they would want from role-playing and perhaps not what they want from their fiction. Maybe that would take people out of it.
The sex act in itself often times is an act of male dominance, be it a consensual one. I see 'Rape fantasies' as perhaps simply taking that to its extreme form. It's an extreme form of male sexual dominance.
It's also interesting that this is seen as pretty much Twilight fanfiction. I kind of see the eroticism of vampires in a similar way. A vampire is an extreme expression of masculinity and male sexual dominance. There is something dark and dangerous about a vampire. That becomes something very seductive.
