In this school fantasy set in the distant future, creatures contaminated by pollution have overtaken the land, forcing humanity to live in isolated mobile cities known as Regios. One such city, Zuellni, is a self-contained school where freshman Layfon Alseif has just enrolled. Layfon reluctantly joins the 17th Martial Arts Studies Unit, led by third-year student Nina Antalk, and embarks on a series of adventures.