The online game "YGGDRASIL," which swept the gaming world, suddenly and without warning, ceased all services. Or so it should have. But for some reason, it became a game where even after the end time, the player characters would not log out. NPCs began to have their own thoughts. In the real world, an ordinary young man who loves video games, along with his entire guild, seems to have been transported to another world, becoming the strongest magic caster with a skeleton appearance, "Momonga." He and his guild "Ainz Ooal Gown" will begin an unprecedented fantasy legend!