Night Classics

Anyone know anything about Night Classics? I have several and they seem to be piracies of some sort or another. I'm currently reading one called "Madame Yes". (By Willis Carlisle) The title has very little to do with the subject of the book, cocksure-private-eye-goes-to-investigate-murder-at-a-mansion-beds-many-women. The other title I have is called "Madame Nemesis" (Julien Du Pont) and, if memory serves, starts out with a surfing scene. This line of books have blue, black and white covers with line-art drawing of sprawled nekkid babes on the covers. No publishing info or dates. They don't appear to be piracies from Pioneer but have a weird "Neva" look to them. Odd, but somewhat interesting.