Sometime in the distant future, mankind is forced to live in domed cities while the rest of the world is left to recover from years of environmental hardships. In the Siberian Dome-polis, professional gamer Gainer Sanga and mercenary Gain Bijou commandeer an Overman and lead a mass exodus out of the city.

Katari, a young girl who dreams of becoming a novelist, writes a love letter to a boy at her school. Unwittingly, she is creating a "short story" that will move a little girl's heart.

More than twenty years ago, an evil summoner committed "Great Summon". One third of human beings were killed, and devils and monsters invaded the Earth. One day, a painter, Tamura Fukutaro, moves into an apartment house called "Ashiaraiyashiki" and gets involved in the troubles of his non-human neighbors. It's the beginning of a severe battle among gods, devils and the ruler "The Central".

A year has passed since the Star Force returned to save the Earth but another danger now approaches from deep space. A gigantic White Comet hurtles toward our galaxy, obliterating everything in its path. But it is no ordinary comet—it is the deadly Comet Empire, conqueror of worlds... and Earth is the next target! Against orders, the Star Force blasts off to investigate, but even if they can get past the flagship Andromeda, they don't yet know the true nature of their new enemy! (Source: AniDB)