Why are you so determined that Hitler and friends had to have been demons? Is it that if they were just ordinary men committing and authorising evil acts, then the same could be said of anyone? Or is there another motive?
At the age of five, Skagra decided emphatically that God did not exist. This revelation tends to make most people in the universe who have it react in one of two ways - with relief or with despair. Only Skagra responded to it by thinking, 'Wait a second. That means there's a situation vacant.'