Chisato's journey home from Manchuria after the war.

The story begins in the future when Earth itself is no longer inhabitable by living creatures. Humans began their interstellar migration with space colonies. Vince and Hana work as researchers in the Cambrian Project. Together with the creature Pikaia, they seek the Lost Code, the key to restoring Earth, and aim to return to Cambrian-era Earth.

Kato, Shimura, Arai, Nakamoto, and Takagi are friends at an all-boys boarding school. After they get tricked by their school government president, the five must put on a performance of the play "Little Women."

The story of a young girl and a young dragon. Naturally, they are the best of friends, and naturally the rest of the world is against them both. However, when demons decide to trash their world, they side with those who have always been against them.