Wait......this isn't just "erotica", but actual game content as well? Surprising ^_^
I've only seen a few 'Sex in D&D' books over my lifetime (from the old unofficial 'Homebrew' from WAY back, to the infamous 'Book of Erotic Fantasy' for 3rd Edition (forced Wizards of the Coast to change their 3rd party guidelines, but not before it had the 'official' stamp of a 3rd Party product for D&D ^_^)
Decided to go ahead and buy the PDF (plus a couple of bucks), gotta support those who try to add good naughty rules to the game ^_^