Japanese businesses struggle after steep goals for greenhouse gas emission reduction are set. However, something rises to their aid. Monsters called "Prana" evidently have the ability to purify air. People blindly put their faith in the Prana, but their size grows.

In the middle of a tense transgression, a massive being suddenly appears in the sky. The being calls itself Argos, and gives the people an ultimatum. Who will they sacrifice? The terrorists and the citizens? Or the prime minister? The entire nation is asked to cast their ballots and decide, in the name of democracy.