Thanks! The mechanics themselves will definitely be used again, since it worked even better than I was expecting them to (and I haven't had any negative feedback other than regarding the intentionally rancid, demonic buckshot roulette/cloverpit vibes I was going for).
As for it being its own game, I don't see why not. And you predicted what the gameplay loop would be basically to a T. Unlocking new parts/starting bases as you progress (traditional succubi, incubi, hellhounds, shades, slimes, alternates, etc), building a body for yourself for more animations (with just as many customization options), and fulfilling certain requirements for custom orders.