Especially if the idea that the Inverse Fire might keep the Nonmen somewhat intact.
I like that idea. Time to parasitize on it! Without measure and in a big way!
1) Fire, as a mundane image, is a dangerous phenomenon because of it's especial capability to damage the skin -- to violate the most physical and visible border between someone's conciousness and the world.
2) Inverse Fire, as an opposition of a said image, flashes out from the deepest chasms of conciousness. But what riverbeds will that "mind magma" flow? Will it burn things like neurons & memories or interaction will be benevolent (remember the whole inversion thing)?
3) I'm betting on "optimising the mind" scenario. Sentient beings with Inverse Fire have no redundancy or inefficiency in their conciousnesses -- that includes things like remorse and empathy or crappy memory system which is prone to overflow with years.
So, that is it. Inverse Fire is just a hotfix for bugs introduced by immortality patch and cunuroi were just so inept at updating.