I was dating a girl once that loved being tied down and wanted me to act like I was rapeing her. I was a little apprehensive about it at first but after doing it we both loved it. We always had a code word to mean stop(i think it was bananna or something like that) but she never used it. She would always want me to talk really dirty to her and call her things like "dirty slut" and "cunt" and anything to make it more intense. I have to admit it was pretty damn hott, and some of the best sex I've ever had.