There's Night Games Mod ("NGM"), on the fenoxo or tfgames forums I guess, not updated in years as far as I know. Buggy as hell but adds a bunch of content based on deepening addictions/fetishes with each girl
Aside from that there was a small mod called "morepegging" which let you choose a weakness trait at the start to make pegging more likely. I can't remember who originally made it, but I re-implemented it and extended it with a bunch of things like extra flavour text during combat moves, more win/loss scenes (for every character IIRC, and everyone who needs one will buy a strapon eventually, even cassie and kat), more loss/submissiveness tracking and slightly responsive text as a result, also a facesitting stance which has interactions with succubi/pheromones although I think it's rare for enemies to bother using it.
You must be registered to see the links
Sorry that it's a bit of a mess, but yeah, if you broadly know how to use git and an IDE, grab the latest commit from there, add images to the appropriate folder if you want (you can open a .jar file of original night games as a .zip and grab the images!), then run. It's branched from a couple of versions back, also, so it doesn't have the newest character
