The final hour of the popular virtual reality game Yggdrasil has come. However, Momonga, a powerful wizard and master of the dark guild Ainz Ooal Gown, decides to spend his last few moments in the game as the servers begin to shut down. To his surprise, despite the clock having struck midnight, Momonga is still fully conscious as his character and, moreover, the non-player characters appear to have developed personalities of their own! Confronted with this abnormal situation, Momonga commands his loyal servants to help him investigate and take control of this new world, with the hopes of figuring out what has caused this development and if there may be others in the same predicament.

Equally charming and stern, Heine Wittgenstein is a brilliant man who commands respect, despite his short, childlike stature. Thus, the king of Grannzreich has called upon Heine to undertake a daunting task that has driven away many before him—become the new royal tutor to four princes who are in line for the throne. The four heirs each have very distinct and troublesome personalities: Licht, the flirtatious youngest prince; his immature older brother, Leonhard; Bruno, the studious third prince; and Kai, the oldest of the four and the most reserved. Hilarity ensues as Heine attempts to connect with each of the princes in order to groom them for the throne. However, Heine's mysterious past and dark undercurrents in the present may threaten the harmony within the kingdom.

With no more death flags in sight, personable but dense Catarina Claes is finally able to lead a peaceful life surrounded by all of her friends and family. For that reason, she is determined to enjoy the school festival to the fullest without any concern on her mind. Unbeknownst to her, however, the story of Fortune Lover—the game she used to play—has yet to end. Even more characters make an appearance, each with their own agenda to fulfill, and new mysteries await Katarina and those she loves. Will there be any way to avoid a bad ending when Catarina cannot remember what happens next?

Following the horrific assault on the Re-Estize capital city, the Guardians of the Great Tomb of Nazarick return home to their master Ainz Ooal Gown. After months of laying the groundwork, they are finally ready to set their plans of world domination into action. As Ainz's war machine gathers strength, the rest of the world keeps moving. The remote Carne Village, which Ainz once saved from certain doom, continues to prosper despite the many threats on its doorstep. And in the northeastern Baharuth Empire, a certain Bloody Emperor sets his sights on the rising power of Nazarick. Blood is shed, heroes fall, and nations rise. Can anyone, or anything, challenge the supreme power of Ainz Ooal Gown?