The Emperor reigns as the central antagonist and game master of the lethal survival contest, Tasūketsu. This entity initiates the game by posing daily binary questions through electronic screens, imposing the core rule that participants selecting the majority answer face instant death. Survivors avoiding the majority vote endure, competing until the last remaining participant earns the right to personally challenge the Emperor.
The Emperor's origins and motivations remain concealed across all media. The character operates exclusively through the game's mechanics, manipulating events from an unseen position of absolute authority. Participants gain special supernatural abilities, known as "Privileges" or "Rights," by sacrificing body parts. These powers become vital tools for survival within the game and for opposing the Emperor's control.
In the narrative's climax, surviving players ultimately confront the Emperor. The resolution employs time travel to prevent the Emperor's descent into antagonism, revealing the character's actions stemmed from being "in a bad state of mind." This intervention resets the timeline, erasing the game's occurrence and restoring all deceased participants to life.