Sentan Island, surrounded by the peaceful Yuden Sea, exists in a tranquil state, isolated from the war that ravages between the Northern Government and Southern Continent Free Zone. Living on this small island with his mother Fusa, our protagonist Akiyuki Takehara is separated from his father, the town's doctor Ryuzo, yet their bond remains strong. Akiyuki is heading to school after delivering his father's usual lunch when an explosion, involving his friends Haru and Furuichi, engulfs him and produces an enigmatic light that causes unbearable agony in his arm. Despite the lack of understanding, a white-haired girl who was his bus companion leads him to a never-seen-before power.