Em 2045, duas crianças nascidas na Lua e três da Terra precisam fazer de tudo para sobreviver após um acidente na estação espacial.

Yusuke Yotsuya is transported to an alternative game-like world. He becomes a third player and sets out on a dangerous quest with his classmates Iu Shindo and Kusue Hakozaki, who were transported there before.

Because of a plane crash - starting today, we're spending the springtime of our lives on a desert island.