Condoms

A teenage boy who is a virgin is told by his long time girlfriend that they will finally have sex. But first she tells him, he must buy condoms.

Off he goes to the drug store where he study's the rows and rows of different types of rubbers. He finally chooses the style he thinks will pleasure his girlfriend most and redfaced makes his way to the checkout counter.

The clerk rings in the boys purchase and says "That will be $5.99 plus tax".

"Tax?" the shocked boy says. "I thought they stayed on by temselves."