Four months after the Mugen Train Incident, Kamado Tanjiro and Nezuko returned to the Butterfly House after completing their mission, and they met Tengen Uzui, who tried to forcibly take away Kanzaki Aoi. Tengen Uzui let Aoi go at Tanjiro's request, and then agreed to the request of Tanjiro, Gasai Zenitsu and Hashibira Inosuke, and let the three sneak into Yoshihara Entertainment District instead of Aoi, and split up to find his wives Suma, Makio and Hinatsuru who was missing because of the sneak investigation of the evil spirits.
Under the investigation of the three people, it was found that the identity of Entertainment District's popular oiran was the land of the "Twelve Ghost Moons", Daki, but Zenitsu was captured by the Daki. After learning about the incident, Uzui felt guilty and asked Tanjiro and Inosuke to leave Entertainment District immediately. As Tanjirou prepared to leave and join Inosuke, he found the trail of the Daki and engages her. On the other hand, Inosuke, who couldn't wait for anyone, found a ghost hiding in the ground, so he got into the ground and found the imprisoned Zenitsu, Makio, and Suma, as well as the ghost guarding them. After rescuing them, Inosuke fought the Belt Demon with them, and the latter is also defeated by Uzui, who arrived later.
After the fight, Uzui, who was seriously injured, decided to retire; Ubuyashiki Kagaya, who learned the result of the battle, was overjoyed and believed that this generation would definitely defeat Kibutsuji Muzan. On the other hand, due to the killing of the string, Akaza and other members of the twelve ghost moons were summoned to the infinite city...
