When Jack Kirby joined DC Comics in the early 1970s, in his big exodus from Marvel Comics that brought us the Fourth World books, he was full of ideas. One of the things he pitched to DC editor-in-chief Carmine Infantino was non-comic book sized projects aimed at adults. This resulted in the comics magazines Spirit World and In the Days of the Mob, but also numerous never realized projects. One of these was an "underground" comic that would be tabloid sized under the title "Uncle Carmine's Fat City Comix." It would be a monthly anthology book, and he talked to creators like Steve Ditko, Wally Wood, and Harlan Ellison. Kirby himself was working on an "adult" themed strip titled "Galaxy Green." When Spirit World and In The Days of the Mob both failed at the newsstand, many of these other non-traditional ideas were not taken any further. I have not found evidence that any work beyond Kirby's Galaxy Green pages and some mock-ups for a presentation that Infantino may never have looked at.
Cooke, Jon B. and Steve Sherman. "Jack Kirby's Superworld." Comic Book Artist Special Edition No. 1. TwoMorrows Publishing.
Michelitch, Jason. "Jack Kirby's Erotic Flirtations: The Sensual Side of the King of Comics." Comics Alliance, Feb 24, 2012. https://comicsalliance.com/jack-kirbys-erotic-flirtations-the-sensual-side-of-the-king-of/ Access Aug. 30, 2022