Cumming on a complete stranger, who doesnt want that? Ok, there might be clothes between but still its very hot. Allthough its horny and exciting you still need the balls to do this, you dont want to get caught. Next to that you cant cum on command, sometimes it takes a little bit longer then other times. Every time when he is almost there she starts moving and he has to stop and eventually he shoots his load in her hand in stead of on her ass.