This was posted on the groaners listserv. The author is not known.

An older gentleman often used to go golfing by himself and would team up with anyone who was available. One day he was teamed up with a lovely blond lady. They very much enjoyed their round together and met quite often afterward for a game.

Finally, the gentleman decided he had fallen in love with the young lady and asked her to marry him.

She said, “But you don’t know anything about me. You know, I am a hooker.”

He said, “That’s ok, just straighten out your wrist and move your thumb a little.”