After a string of mysterious disappearances begin to plague a train, the Demon Slayer Corps' multiple attempts to remedy the problem prove fruitless. To prevent further casualties, the Flame Pillar, Kyoujurou Rengoku, takes it upon himself to eliminate the threat. Accompanying him are some of the Corps' most promising new blood: Tanjirou Kamado, Zenitsu Agatsuma, and Inosuke Hashibira, who all hope to witness the fiery feats of this model demon slayer firsthand. Unbeknownst to them, the demonic forces responsible for the disappearances have already put their sinister plan in motion. Under this demonic presence, the group must muster every ounce of their willpower and draw their swords to save all two hundred passengers onboard. As things begin to spiral out of control, Tanjirou's resolve and commitment to duty are put to the test.

Ever since the death of his father, the burden of supporting the family has fallen upon Tanjirou Kamado's shoulders. Though living impoverished on a remote mountain, the Kamado family are able to enjoy a relatively peaceful and happy life. One day, Tanjirou decides to go down to the local village to make a little money selling charcoal. On his way back, night falls, forcing Tanjirou to take shelter in the house of a strange man, who warns him of the existence of flesh-eating demons that lurk in the woods at night. When he finally arrives back home the next day, he is met with a horrifying sight—his whole family has been slaughtered. Worse still, the sole survivor is his sister Nezuko, who has been turned into a bloodthirsty demon. Consumed by rage and hatred, Tanjirou swears to avenge his family and stay by his only remaining sibling. Alongside the mysterious group calling themselves the Demon Slayer Corps, Tanjirou will do whatever it takes to slay the demons and protect the remnants of his beloved sister's humanity.

The devastation of the Mugen Train incident still weighs heavily on the members of the Demon Slayer Corps. Despite being given time to recover, life must go on, as the wicked never sleep: a vicious demon is terrorizing the alluring women of the Yoshiwara Entertainment District. The Sound Hashira, Tengen Uzui, and his three wives are on the case. However, when he soon loses contact with his spouses, Tengen fears the worst and enlists the help of Tanjirou Kamado, Zenitsu Agatsuma, and Inosuke Hashibira to infiltrate the district's most prominent houses and locate the depraved Upper Rank Demon.

Based on a manga Noroiya Shimai written by Hirarin and serialized in Monthly Comic Ryuu. It is a story about a pair of sisters who work as noroiya (cursers) using magic in a fantasy world. One day a big tree suddenly appears in a forest, and tall buildings that look like they are from our world can be seen entangled in it. The two sisters go there to investigate and get ported to our world. They then encounter two children who are startled by the sisters' sudden appearance and rush back home but at home they see their parents turned into monsters... (Source: MAL News)