I'm assuming not much of the conversation goes to his endowment, right? Or does it? If not, then what else do they talk about?
EDIT: AFTER the sex, when (if) the girl talks about the experience with her friend(s).
One possibility: "Oh by the way honey, I was at the PriceChopper today and that checkout girl LaVulture says she's going steady with a man who has a gorgeous peice of manhood and it's nearly 80 feet long. Anyway her cousing Fred is getting married to the woman who teaches art over at the middle school."
Possibility-#-2: "Honey, are you alive, I don't feel you moving right now. Which reminds me, there was a show on HGTV about this couple that moved into a really nice house with an outdoor jacuzzi and it even had a gazebo out back."
Possibility-#-3: "Honey, did you know that there are more people living on Elm Road than there are on Elm Parkway? Oh, and I have an appointment with the nail salon Saturday so you'll have to take Lori to the girl scout meeting."
There are all sorts of things they can talk about--