What is a pussy?

A boy is at school and he hears the older kids talking about pussy, and their bitch. The boy confused by this goes to his mother. Mom, the boy asks, What’s a pussy?
The mother being startled by this thinks quick and finds the closest dictionary and opens it up to a picture of a cat and says Son, that is a pussy. the son then asks What’s a bitch? The mother again thinking quickly opens to a picture of a dog and says Son, this is a bitch.
The son walks away still confused, and sees his father watching television. The son walks up to his father and says Dad, what’s a pussy? The father doesn’t want to miss the baseball game so he quickly whips out his Penthouse magazine to the centerfold, grabs a marker and draws a circle around the vagina and says Son, this is a pussy!

The son, now starting to understand what the older boys are talking about asks Then, what is a bitch?
The dad replies, That’s everything outside the circle.