The aim of the Prison Town is to detain and rehabilitate creatures with criminal records. However, Akari Sakuragi, a human who accidentally dozes off on a train, is incarcerated for trespassing, despite not being a convict. In order to secure her freedom, Akari must inhabit the space with the monsters and collaborate with them. Every resident must be paired with a partner to boost their morale.
Mary, a quiet, artificial being famous for her diligence, is designated as Akari's teammate. Akari is struggling to adapt to the bizarre tasks assigned to her, which are vastly different from her usual routine. Despite having contrasting personalities, Akari is inexplicably drawn to Mary and makes an effort to comprehend her deeper. Nevertheless, when Akari discovers why Mary is confined to the Prison Town, how will she react?
