During a school computer class, Saneatsu Narita encounters a strange screen displaying a yes-or-no question that vanishes quickly. The following day, Saneatsu awakens to a world where everyone, except himself and a few others, is dead. An announcement from a mysterious figure known only as the Emperor begins to clarify the situation. The question Saneatsu saw on the screen is part of a game called Tasuuketsu. Each day, the survivors will see a question appear on a screen, and their answer will determine who lives to see the next day. Answering the same as the majority guarantees death, and the last player standing earns the right to meet the Emperor. Saneatsu resolves to beat the Emperor at their own game, utilizing 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.