22 years ago, Yokohama experienced an inexplicable seismic occurrence that led to its separation from mainland Japan and its ascent into the sky. Over time, a certain section of the inhabitants procured unprecedented abilities that were distinct to their temperaments, and they came to be known as Alters. These Alters plunged the formerly prosperous city into chaos. Currently, as Yokohama recovers, the Alters are divided into two factions - the HOLY, an organization with ethical principles and a plan to restore order, and those who intend to subjugate the weaker, regular populace. In the midst of this tension, Kazuma, a robust Alter who values himself and an orphan girl Kanami, finds himself stranded. He distrusts both groups and is oblivious to the fact that he may hold the key to achieving harmonious coexistence.
