Synopsis
Ordinary high school student Aoba Watase is suddenly attacked by a giant robot called a "Valiancer," only to be rescued by his mysterious classmate Hina Yumihara. After revealing that both she and the enemy robot come from the future, Hina sends Aoba seventy years forward in time to save his life. Arriving in the future, Aoba finds himself inside the cockpit of a Valiancer named "Luxon," right in the middle of a battle between the military forces of the Free Pact Alliance (FPA) and the Zogilia Republic. When he demonstrates a strong compatibility with FPA pilot Dio Weinberg, the two successfully execute a "coupling," enabling them to share experiences and thereby boost their abilities and skills. Though Aoba manages to survive the unexpected fight, he is taken into custody by the FPA ship Cygnus for questioning. While the student's main worry is whether he can ever return home, he has no idea that he is about to become entangled in a war to save the world.