What metaphors are used in The Schwa Was Here by Neal Shusterman?

The reader sometimes forgets what is going on with the Schwa because Antsy holds their attention, which perfectly demonstrates the Schwa effect in action. The Schwa effect is something between a supernatural force and a metaphor. It is a mysterious and unusual effect that has been stretched beyond what is normal in order to create a fun story with supernatural elements to it. However, it is also a metaphor for all the 'invisible' people in the world. These are people who feels ignored and let down constantly by others. They are the forgotten people whom society does not seem to care about. The Schwa is one of these.