(slightly OT)
Sounds like a challenge!
My submission: 20% neem, 10% laurel, 40% MCT or fractionated coconut/PKO, 10% dairy butter, 20% salvaged HL sunflower oil (used just a bit too long for deep-frying sea fish). Scented with a ton of chili pepper and cinnamon EO.
I wonder who would love such a bar of soap? On the other hand, it would quite certainly “surprise” any unprepared user, so it's not entirely wrong in this thread.
I hate it already, and it's not even made yet. Good job!