Where does the 3000 amount come from? LonaRPG uses a paperdoll system for Lona. In other words, the art isn't done from scratch for each pose Lona is in. There isn't a full drawn scene for each scene of Lona on her back with different levels of dirtiness, it just applies a dirtiness layer to pre-existing art. Same thing with clothes, piercings, and pretty much every status effect.
In other words: all it'd actually need is adding a futa status effect and adding a layer with genitals. Code wise it'd need to disable vaginal as an option and if you want to make it a bit more unique feeling, have Lona take the dom/male poses when juicing. In other words, it'd need to add said genitalia for each pose, plus the main doll, and on the nude pixel sprite. Excluding the pixel sprite, that's maybe 20 dicks, plus Deep One variants, but you could just disable it for the Deep Ones due to their backstory.