The narrative unfolds in a world where humanity persists in its war against the "unknown," an enemy of mankind. Children who were evacuated to a cryogenic sleep facility during the invasion by the "unknown" several decades ago awaken from their slumber to discover that their bodies have developed certain supernatural powers. To protect the nation from the "unknown" emerging from the Tokyo Bay gate, these boys and girls engage in battles to defend the cities of Tokyo, Kanagawa, and Chiba.