Eaten up with guilt, shame, fears and insecurities and obtaining, if he's lucky, a barely perceptible physical feeling, the male is, nonetheless, obsessed with screwing; he'll swim a river of snot, wade nostril-deep through a mile of vomit, if he thinks there'll be a friendly pussy awaiting him. He'll screw a woman he despises, any snaggle-toothed hag, and, further, pay for the opportunity. Why? Relieving physical tension isn't the answer, as masturbation suffices for that. It's not ego satisfaction; that doesn't explain screwing corpses and babies.