I agree with Valise.

3-4 hours of just sex sounds like too much. I've gotten my d**k raw from having too much before, and it's doing stuff like that that did it. Actually, I've had it happen twice. D:

Anyway, foreplay included, it can last at least an hour and a half, usually more. But nothing but just sex for 4 HOURS? Pass. My favorite part is the foreplay, then the sex is just AMAZING.