Get it?

A middle aged man was shopping in his neighborhood supermarket when an attractive woman approached him. She stopped in front of him and said "Hi." He smiled and then asked if he knew her. She quickly said that while he might not remember her, he was the father of one of her kids.

Shocked, he tried to remember her but finally asked if she was the only woman that he had ever cheated on his wife with. "Are you the stripper at my bachelor party that I made love to on the pool table in front of all of my buddies while your stripper partner beat my ass with celery sticks?" "No" she said. Your son is in my math class.