Combine corrupt bonemeal and vile ashes and the result is demonic oil. We should be specific about what kind of oil this is: please do no pour it into a frying pan or use it on a squeaky hinge. This is potent oil, as the 'demonic' prefix will attest. It is used for crafting, and solely for crafting.
Now you've got us wondering what would happen if you did actually add it to a frying pan or a squeaky hinge. Obviously, please don't do it. But if you do happen to do it, through an accident or momentary lack of wisdom, could you let us know what happens?