No.6

After a devastating world war, humanity lives inside model city-states supposedly built to guarantee safety and perfection. Shion grows up among the elite of No. 6 until his twelfth birthday, when he shelters a fugitive boy named Nezumi. That choice costs Shion his privileges and relocates him and his mother to the city's outskirts, but it also leaves him with the doubt Nezumi planted about the perfect society he was raised to trust.

Years later, a series of mysterious deaths leads to Shion being accused of murder, and Nezumi suddenly returns to rescue him from arrest. The two flee into the impoverished settlement beyond No. 6, where Shion sees for the first time the real price of the city's comfort. Their search for the cause of the deaths leads toward a secret at the heart of the system itself, forcing Shion to decide whether he can protect the people he loves from a city that once defined everything he understood as home.