M19 and I've had a steady girlfriend for about a week now. We had a friends-with-benefits situation for three months before that, and last week she asked if we could make it official. Our sex was great before, but now I just can't finish. Sometimes we go at it for two hours, but usually it's between four and five hours. No joke. Because I can't finish, I'm constantly horny. We take breaks, but we start up again pretty quickly. At first, I thought it was awesome to be able to have sex for hours, but now my dick really hurts. I've even got a bruise now. If it were up to me, we wouldn't go at it for so long, but she just doesn't want to stop. If we take a break, I'm busy fingering or going down on her. I think the only way it'll end is if I finally finish, but I just can't, no matter what position we try or how long she blows or jerks me off. I'm so desperate that I want to try MDMA with her because I've heard sex on it is amazing, and maybe then I’ll be able to finish.