Rape fantasies used to be standard fare in romance novels until about thirty years ago, when someone finally noticed that readers preferred books without them than with. So whether or not they are "normal" depends on the age of your book collection.

Nowadays you'll still find a lot of scenes where the woman "gives in to her desires" against her better judgment, but usually that's because of a conflict between her lust and the belief that the guy she's hot for isn't the right guy for some reason (which then drives the rest of the book).