In the year 2071, the Far East is ruled by angry gods. 20 years ago unknown life forms called “Oracle cells” begin their uncontrolled consumption of all life on Earth. Humanity both fears them and reveres them as "aragami." They are immune to all weapons and the mankind's numbers continue to dwindle. The last bastion of hope is the newly developed "God Arcs" weapons that utilize Oracle cells to fight back. The weapons wielders band together into an elite force dubbed "God Eaters."

Set in Japan in the year 2071 where the world has been mostly destroyed by mysterious monsters known as the Aragami. An organization known as Fenrir was made to exterminate Aragami using weapons called God Arcs which is made from the cells of an Aragami. Those who specialize in exterminating Aragami are known as God Eaters. Originally God Eaters had one type in which their God Arcs can only keep gun form or blade form, however a new type has been discovered that can switch between gun and blade form. Since then, they have been classified new-types and the previous as old-types.