"Hey, Mom, can I sleep over at my girlfriend's house?"
UPDATE: Over at Matt Yglesias's blog, cd asserts
it's possible that the parents of a son, in particular, are trying to teach him that regardless of what his dick is telling him to do, there are ways to show respect to his own and his girlfriend's parents, not to mention to his girlfriend herself, that may involve a measure of self restraint.One of the reasons I hate that "Promiscuous" song is because it perpetuates the idea (which cd may be implying here) that having sex with someone means you then do not respect them. So: what respect is shown to the girlfriend here if the son restrains himself? Presumably she's consenting.