Good: You are making out with your girl in a car in a dark corner of a public park.
Bad: A cop car pulls right next to you and switches its lights on.
Ugly: Your girl says, "Oh my god, it's Dad."
Good: Your wife decides to give you a lap dance for your birthday.
Bad: She moves like a professional.
Ugly: You tip her a twenty and she looks disappointed.
Good: Your teenage daughter comes to you for advice.
Bad: About sexual positions.
Ugly: Involving more than one partner.
Good: Your daughter writes home from Hollywood saying she made it into the movies.
Bad: As an extra.
Ugly: You find the movie in the backroom in an adult video store.