Yes, the art is AI, made with stabilityXL. I noted it in credits and itch page (just to reassure that I wasn't trying to hide it!). I got a kick out of appending demonic:10%, demonic: 50%, etc to Bob to see how he morphed.
Thanks for the note about the music loop. I definitely do want to fix that. Twine has fairly rudimentary music controls, so I'll need to bug the musician for some fading (or learn how to edit music, heh).
The menu is another thing I agree is meh. I struggled to figure out which CSS elements twine needs to target for things like sliders (there is code there for styling, but it's not applying properly, I'll need to deep dive to figure out how) and eventually decided it was lower priority than other parts of the game.
Thanks for playing and for the feedback!