A farmer walks into his bedroom with a sheep on a leash and says, "Honey, this is the cow I make love to when you have a headache."
His wife, lying in the bed reading a book, looks up and says, "If you weren't such an idiot, you'd know that's a sheep, not a cow."
The guy replies, "If you weren't such a presumptuous bitch, you'd realize I was talking to the sheep."