A girl wants to borrow her father's car, so she goes downstairs and asks: "Dad, can I take the car tonight?"
On which her father replies: "Only if you give me some head first"
His daughter is appalled, but seeing as she has an important date tonight, she decides to comply to his wishes. She goes down on her knees, pulls down her father's pants and stares at his penis.
"Dad, you've got shit on your shaft"
"Ow that's right, I almost forgot. Your brother has the car."