Quote from Rachel in The One with Phoebe's Uterus
Monica: Everybody knows the basic erogenous zones. You got one, two, three four five, six and seven. Chandler: There are seven? Rachel: Let me see that. Oh, yeah. Chandler: That's one? Monica: Kind of an important one. Chandler: Oh, you know what, I was looking at it upside down. Rachel: Well, you know, sometimes that helps.