Known for its vast freedom, Yggdrasil is a virtual reality game where players can freely customize their classes and weapons. As the game's servers prepare to shut down in 2138, Momonga, a dedicated player, remains in his guild, Ainz Ooal Gown, for its final moments. To his surprise, he doesn't disconnect at midnight; instead, he is transported to a world resembling Yggdrasil, where NPCs have gained consciousness. Trapped in a skeletal form, Momonga embarks on a quest to understand his situation, unite with fellow players, and seize control of this new realm alongside his loyal followers.