It isn’t premarital sex if you have no intention of getting married.

An elderly man and woman meet in a bar and get to talking. They are enjoying their conversation so much that, when the bar closes, they decide to continue at the woman's apartment. After a time, things start getting pretty romantic and they wind up in bed. Afterward, they're both laying there, staring at the ceiling. The old man is thinking, “Gosh, if I had known she was a virgin, I would have been more careful with her.” The old lady is thinking, “Geez, if I had known he could get it up, I would have taken off my panties.”

Two policemen are walking the beat when one says, ‘When I get home, I’m going straight upstairs and tearing off the wife’s underwear.’ ‘Feelling randy?’ asks the other. ‘No,’ says the first. ‘The elastic is killing me.’

Two men are having a drink together. One says, ‘I had sex with my wife before we were married. What about you?’ ‘I don’t know,’ says the other. ‘What was her maiden name?’

If sex is such a natural phenomenon, how come there are so many books on how to do it?