Yu-Ching Fei's joke, how did 67 blond hair come from?

The wife stood naked in front of her husband, who stood behind her. Wife: Take that first. Husband: Yes. Honey, can you bend forward? I don't feel well. My wife bent forward 90 degrees. Wife: Are you excited this time? Husband: I am full of energy. Honey, it may hurt, but I will be gentle. You must put up with it. Wife: Stop dawdling and hurry up. ..... I said can you use some force, didn't eat you? Husband: Aren't people afraid of your pain? Wife: How can you wipe the dust off your back without hard work?