A guy meets this girl in a bar and asks, "May I buy you a drink?"

"Okay. But it won't do you any good."

A little later, he asks, "May I buy you another drink?"

"Okay. But it won't do you any good."

He invites her up to his apartment and she replies, "Okay. But it won't do you any good."

They get to his apartment and he says, "You are the most beautiful woman I have ever seen! I want you for my wife."

"Oh," she says, "that's different. Send her in!"