In the far future. The population of the Earth began to fall after reaching its peak. AI was created to aid in the preservation of species and the management of the environment; it was a big experiment in human diversity. A varied range of individuals, including beastfolk, magical creatures, and others, were produced through genetic engineering to dwell in a diversified metropolis divided into walled "clusters." Each cluster developed its own culture, which reflected the individuals that lived there. The AI is constantly monitoring their life and the system to ensure their existence.