In a distant future where humanity has colonized space, the Earth is torn between the Atlantic Rim United States (ARUS) and the Dorssia Military Pact Federation at war. Amidst this conflict, Japan and the Oceanian Republic (JI0R) stay neutral. The peaceful life of 17-year-old Haruto Tokishima in a JIOR colony is disrupted when Dorssian forces invade, seeking the powerful Valvrave weapons hidden within his school. Haruto, facing a dire situation, discovers a Valvrave and forms a contract that sacrifices his humanity for its power. Teaming up with L-elf, a mysterious Dorssian strategist, they embark on a revolution to change the course of the world.