He takes forever to cum..

Okay so I've met this guy and he is an absolute sweetheart! He was a virgin before I came along anyway.. So he takes forever to cum and always ends up feeling like I dry up really quickly. It's so annoying. I keep thinking it's because of the soap he uses or something? I have no idea because it's not like I'm not turned on by him, it just becomes painful. And it's not a STD or anything because I've only recently had a check up. But am I doing anything wrong for him not to cum? I work my ass off to try but it just doesn't work, even when he's masturbating it takes him a while.. Is it just him? And could the soap he uses be making me dry?