The Knob (adult humour)

A woman in her late forties went to a plastic surgeon for a face-lift.
The surgeon told her about a new procedure called “The Knob”, where a small knob is placed on the back of a woman’s head and can be turned to
tighten up her skin to produce the effect of a brand new face lift. Of course, the woman wanted “The Knob.”
Over the course of the years, the woman tightened the knob, and the effects were wonderful - the woman remained young looking and vibrant.
After fifteen years, the woman returned to the surgeon with two problems.
“All these years, everything has been working just fine. I’ve had to turn the knob many times and I’ve always loved the results. But now I’ve developed two annoying problems: First, I have these terrible bags under my eyes and the knob won’t get rid of them.”
The doctor looked at her closely and said, “Those aren’t bags, those are your breasts.”
She said, “Well, I guess that explains the goatee.”