This is an interesting topic.

I think the reason that the victim-enjoying-the-rape fantasy is growing into a problem is that the idea's is being overused. This occurrence that's suppose to be rare, at the best, is quickly becoming all too common. And also, as pointed out, there are situations where the victim could never, ever enjoy the rape.

Sure, certain stories might be a tad unrealistic. The giraffe example was certainly not very lifelike. But there are certain settings in which such a twist could work. There are possibilities in which the victim happened to be submissive, or had an orgasm without choice. I agree with Ranai. Under the right circumstances, something like that could be realistic, if done right. It's a long shot, but that's why it's a story.

To me, it all depends on perspective and individual interests. And there's a wide variety where BDSM is concerned. Not everyone enjoys fantasies about savage rapes by vulgar men. Some prefer light bondage and consensual circumstances. As I said before, it depends on the individual. Not all authors will have the same fantasies as you. Let them write what they want. You don't have to read it.