A guy goes to the supermarket and notices an attractive woman waving at him.
She says hello. He’s rather taken a back because he can’t place where he knows her.
So he says, “Do you know me?”
To which she replies, “I think you’re the father of one of my kids.”
Now his mind travels back to the only time he has ever been unfaithful to his wife, and he says,
“Oh, are you the stripper from my bachelor party that I did on the pool table with all my buddies watching while your partner whipped me with wet celery?”
The woman looks sternly into his eyes and says very calmly,
“No, I’m your son’s teacher.”