An environmental catastrophe turns a once-stunning city into a wasteland. Though survivors re-build the city, known as The Lost Grounds, some of its citizens suffer birth defects from the massive radiation. Known as Alter Users, they possess superhuman powers to transform into other forms of matter. Banished outside the walls of the city, the Alters live in the ruins and fend for themselves. An organization known as Holy hopes to cleanse the area of deformed creatures, but Kazuma, an Alter, must choose between the ways of Holy and lifelong imprisonment.