One day little Johnny goes up …

One day little Johnny goes up to his granddad and asks, “Granddad, what’s a cunt?”
The granddad looks at him for a while then goes and fetches one of his old porno mags. He flips it open, pages through and leaves it open on a picture of a naked woman posing.
“You see those stars, Johnny?”
“Yes.”
“Well the person who put them there is a cunt.”