frotteur

A person who practices frotteurism is known as a frotteur.

He is Frotteur.

The term frotteur is the French noun literally meaning "rubber" or "one who rubs" and was coined by sexologist Richard von Krafft-Ebing in his book Psychopathia sexualis (1886).

Both the sweeping and waxing of floors was reserved for a manservant called the frotteur who went tearing about from room to room with brushes strapped to his feet, "dancing here and there like a merry Andrew," and to whom was also assigned the unenviable task of emptying the chamber pots.

It turns out, from Flaubert's travel notes, that the business-card wasn't pinned in place by Monsieur Frotteur himself; it was put there by the lithe and thoughtful Maxime du Camp, who had scampered ahead in the purple night and laid out this little mousetrap for his friend's sensibility.