I recently stumbled on this: Confetti
Its a script that connects Ren'py to connect to a local instance of comfyui to do on the fly image generation based on provided comfyui json workflow. I've found it to be a bit temperamental with tests myself but I figured someone more familiar with renpy might be interested in it and its potential for use in Brothel King as a mod to make brand new images while you play.

Recently I've been putting some time into a Brothel King lorebook for text generation that includes personality profiles for every type of girl. A similar project for local text generation would also be interesting and likely easier to implement (quicker to generate, more likely that the output is of sufficient quality)