I was having sex the other day, and started to get tired, so I told her to "get on top" To which she said, "you haven't raped many girls before have you?"
I am hoping you're not making light of rape by telling a joke like that.
I've worked in the sexual assault and rape center, even the ones that are threatened like this secretly want the rape to happen. They regret nothing.
Telling jokes about rape or saying that women actually do want to be raped is a dangerous way to behave. When people say things like that, they are just encouraging people to actually go out and rape people. Women don't actually want to be raped, and I would suggest reading up on the statistics of rape so you can see just how common it is.