Gods and Demons

Ok, I've been reading through this novel, and there are all sorts of people (if we can call them that) with 'special powers'. Some of which are called "Gods", while others are "Demons". Zelanzy doesn't seem to distinctly separate the two. The "Demons" are punishing and cruel (as what all assume when they hear the word demon). However, some of the gods, such as Brahma, are just as 'evil' seem even more punishing then the Demons. So the big question is, what seperates these Gods from from Demons? Is it the fact that there is a larger number of worshipers for gods and a smaller number of worshipers for demons? Are the demons a result of few followers? Are the demons, demons merely because the popular "gods" have said so? It leaves one something to ponder...