George said to Mary, "I'll bet you ten dollars that we could have the best sex that you have ever had without me touching you."
"You're nuts," she said, "Here is ten dollars that says you can't do that!"
They put the money on the mantelpiece.
That night George and Mary proceeded to have sex. Reluctantly, Mary had to admit that it was the best sex that she could remember. The next morning she exclaimed, "Well, it may have been the best sex I've ever had... but you did nothing BUT touch me!"
George gave Mary the ten dollars and departed with these words, "So I lose."