This is a particularly interesting question because the word “demons” is not really common within this particular novel; however, I assume you mean the creatures that become symbols for different aspects of evil. A symbol, of course, is something that stands for something else, and each of the “demons” here represents a particularly evil quality. The “demons” I will discuss here are the snake, the ogre, and the grubs.
There are three creatures that represent a different aspect of evil in this novel. First, the snake represents corruption. A plastic snake is used by Kamt and Nyawra when they create a disturbance in Paradise. The dissidents also throw pretend snakes at the politicians. When The Ruler is “pregnant” and eventually explodes, he appears with a tongue like a snake. In this case, the snake is truly the demon of corruption, specifically the political corruption within Paradise and Aburria. Next, the ogre represents greed. This is a traditional symbol within African culture. This particular demon is affecting Tajirika. It is not long before his family believes that he has truly changed into an ogre. One of the final proofs of this is that Tajirika decides not to wash the hand that has touched The Ruler and simply covers that hand with a glove. In this case, the ogre is truly the demon of greed. Finally, we need to talk about the grubs that represent capitalism. The “white grubs” appear when Kamt buries the Buri notes in the field and the money grows into trees that sprout American dollars. The white grubs consume the dollars, but are never satisfied. Further, it is very significant that the grubs are specifically white. In this case, the grubs are truly the demons of the insatiability of capitalism.
Even though the word “demons” is not actually used here, a wise person can recognize that the good “Wizard” named Kamt would fight demons in his own country. Kamt eventually fights the demons of corruption, greed, and capitalism in the form of the snake, ogre, and grubs.