Penis Problem

This guy goes out with his buddies for a night on the town and they cap off the festivities by going to a house of ill repute.

A week later, the guy visits his doctor complaining of a large green lump on the end of his penis. The doctor does a thorough exam, then pulls down a weighty medical book and flicks through it till he finds what he's looking for.

He looks up and says, "I'm afraid this is serious. We'll have to operate!"

"Operate?", exclaims the fellow, "Why, Doc? What's the problem?"

"Well, you know how boxers can get a cauliflower ear? You've developed the same sort of thing. You've got a brothel sprout.