Question, how interested would you pack maintainers be in the mod providing the option for a "Nude Body", basically a third directory. Something I liked about the main characters is they have multiple portraits, technically 3 body images, Clothed, Naked Forced, and Naked Consensual. Finding all 3 of those for a portrait isn't as likely, but often you can get both a clothed and nude version of some images, going by what I see on yande.re and danbooru.donmai.us there's options often.
Basically, could tweak the the game so when setting a portrait it sets those if they also exist, and uses them in the sex system like it does for unique characters? Best guess, this would be too much effort to actually setup for any given portrait pack and thus vast majority of portraits wouldn't support it, and thus not too worthy of implementing?