After killing himself, Jean immediately awakes to find himself in the midst of a grand war in a corpse's body. Wearing a soldier's heavy metal armor, he drags himself away from the battlefield despite his agonizing injuries, where M, a peculiar middle-aged man, finds him and takes care of him while he recovers. There, he finds that he has a system, which promises to grant him unparalleled potential in all realms martial, physical, magical, and otherwise ephemeral. His system grants him great power, but can he take it for himself? If so, why? Why not finish what he started and let it all go to waste? But why does this system exist in the first place? What is its purpose? Who is it? What will it take from him? - This story is apocalyptic but only after some story development. - This story largely focuses on Jean's development as an individual. Action and adventure is the majority of the story, but it is just a medium for expressing what he becomes, how it happens, and why.