A youthful wavemaster, known solely by the handle Tsukasa, awakens inside an MMORPG titled The World, suffering mild amnesia. He has no recollection of his actions prior to awakening. Within The World, the Crimson Knights suspect him of hacking, since he was observed escorting a modified character that had taken the form of a cat. Trapped in the game, he roams for clues while evading the knights and other adventurers he encounters.
The game"s reality feels increasingly surreal. He also notices that the world shifts subtly whenever he thinks of leaving. Yet the mysterious guardian offers a promise of safety.
While traversing The World, Tsukasa discovers a wondrous relic shaped like a "guardian," which vows to shield him from all danger. Subaru, the Crimson Knights" commander, together with several players who have met Tsukasa, launch an inquiry into why he cannot log out, striving to resolve the issue before it spirals.