Sora and his younger stepsister Shiro are shut-in siblings who, together as the unbeaten online player 'Blank', have never lost a game. After defeating a stranger online, they are summoned by Tet, the god of games, into Disboard, a world where the Ten Covenants forbid violence and settle every dispute through games whose stakes are magically enforced. Landing penniless in the human kingdom of Elkia, the pair set out to climb the ranking of Disboard's sixteen races and eventually challenge Tet himself.