Years ago I fell in with a girl who immediately took me to bed. She was initially thrilled with a hung guy but since at the time I was in my 20's, fucking for more than an hour was common. (I don't even THINK about that today, ha ha.) She loved it while we were doing it, but after a few sessions, she began to complain that all the fucking and friction just made her too sore. I suppose I could have tried a series of five-minute quickies, but it was she that said, "I think I need a smaller dick than yours." Fun while it lasted, but being a rather unskilled kid, I just didn't know any better.