Sometimes, a gentleman may not want the company of one of the fine ladies at The Nunnery, but rather a pretty young thing to use as a toy. Madame Q must therefore hire dolly mops to fulfill her client's requirements.
A dolly mop is a girl, usually a domestic like a maid, who seeks to earn extra money by occasional prostitution. However, most of these girls have no idea what they're getting themselves in to, imagining dolly mopping as some sort of romantic adventure. This means Madame Q needs a trusted accomplice to introduce prospective dolly mops to the realities of what will be expected of them. When she learns of Dr. Onan's predilections, she realizes that he is the perfect person to break them in.
This is the story of how Mary and Gertie became dolly mops at The Nunnery.