 The fourth novel centers on Aya Fuse, a girl struggling to find her place in the chaotic world after Tally frees people to think for themselves.In humanity's future, a new type of society has been formed after a disastrous oil-bug was released upon the planet that killed 98% of the human population and left many cities in ruins.The new society is composed of about one hundred small post-scarcity, independently run city states, spread out across the seven continents, which now have different coastlines because of modern-societies' global warming.