Toilet Paper

A guy comes home one day to find his wife rubbing milk all over her breasts, curiously he asks her why she's doing this?. She replies that' she has read an article in the magazine that if you rub milk on your breasts they get bigger. He looks at her for a moment and says then you should have used toilet paper. Why asks his wife? He replies; Because it's done a hell of a job on your ass!