During his school computer class, Saneatsu Narita is presented with a strange screen posing a yes-or-no question that quickly disappears. The next day, Saneatsu wakes up to a world where everyone, save for himself and a few others, is dead.

An announcement from a mysterious figure known only as the Emperor begins to shed light on the situation. The question that Saneatsu saw on the screen is part of a game called Tasuuketsu. Every day, the survivors will see a question appear on a screen, and answering it will determine who lives to see the next day. Responding the same as the majority will guarantee death, and the last player standing will earn the right to meet the Emperor.

Saneatsu resolves to beat the Emperor at their own game, making use of the hidden envelopes containing powers that can aid the players. With the help of his small group of friends, Saneatsu must avoid falling into the machinations of the other players and win this wicked game.