Reminds me of this classic:

Really quiet, soft-spoken, polite guy. A total gentleman and a graduate student in the liberal arts. Also, pretty inexperienced, tentative, and vanilla sexually.

He's dating this really cool girl for maybe two months. She is much kinkier in bed. She floats the idea of dirty talk, and apparently likes to be objectified, even demeaned a bit, from time to time. He's hesitant, but wants to please her and doesn't dismiss the idea outright. Changes the subject and figures that they'll revisit the idea another time.

Anyway...they have sex a few days later for the first time since the conversation. Really going at it doggystyle, and she tells him to talk dirty to her. He says that he can't think of anything to say, so he says nothing, and she then repeats the request, but the second time she is not fucking requesting, but demanding it.

He comes up with: "Yeah...you like that, you fucking retard?"

He's never struck me as one for embellishment, so I believe him. He said that was it for sex that night, although they are still together two years on now.