That's the subtitle to my new series of novellas. (What's the word count difference between a full length, a novella, and a short? A question for a different time.) Still menage, still Regency, just a shorter and cheaper story set in the world of the Hellfire Club. These stories are a bit later than the 'traditional' time, but the club has been around, in many incarnations, since Sir Francis Dashwood founded it.
They're set in the late 1790s, the first one during the Reign of Terror in Paris. I've just tweaked the outline and will look it over a couple more times before writing. Never use the first outline! Something always changes.