This sounds like an urban myth but a friend of mine swears it happened to his friend. This particular guy was going out with a girl who was a bit on the wild side. One thing she wanted all the time was to take from behind. But the guy she was going out with didn't like the idea and they never did do it that way. Anyway one night after coming home from a party he was half drunk and she managed to talk him to doing it her way. They went at it, did the deed or whatever. When they were finished and he withdrew and looked down there was a kernel of corn of the head of his cock. He was disgusted. So disgusted that he puked on her back.