Summary: In the year 2061 AD, Japan has lost its sovereignty. The Japanese people spend their days as oppressed citizens after being divided and ruled by the four major trade factions. The country became the forefront of the world following the deployment of AMAIM—a humanoid special mobile weapon—by each economic bloc. One day, Amou Shiiba, a boy who loves machines, meets Gai, an autonomous thinking...

Summary: Japan, 2019, just before the dawn of a new era. Suddenly, a rift to another dimension appears in the sky, revealing an alternative world "Shinkoku Nippon," with the sky and the earth upside down. This parallel world keeps their former militarism, with its era being Eternal Showa. The military invades the real Japan with giant humanoid robots called "Garann" and their gas weapons "Genmu",...