I like scenarios where escape for the girl is totally, absolutely impossible and she knows it. The mounting fear she experiences, knowing that at any moment she will be fucked violently and that there's nothing she can do about it ... delicious fear.
My favorite moment in my fantasies is when the bound girl (she's always bound, preferably in iron or steel), screams when she realizes I've ejaculated into her, rather than pull out and spray it all over her face. The knowledge that she may pregnant with her rapist's child and kept captive until she gives birth driving her to the brink of insanity ...
