After the battle is over, Tanjiro and Nezuko are taken to the Demon Slayer Corps headquarters. This is where the Hashira Meeting between the Corps leader, Ubuyashiki, and the Hashiras, the most powerful swordsmen in the Corps, is to be held. The Hashiras censure Tanjiro for violating the Demon Slayer Corps by protecting a demon. And then, the Wind Hashira, Sanemi Shinazugawa, raises his sword against Nezuko...

Ubuyashiki, the leader of the Demon Slayer Corps, finally appears before Tanjiro. He tells him that he will allow Tanjiro and Nezuko to join the Corps. But the Hashiras are unable to accept this decision right away. The Wind Hashira, Sanemi Shinazugawa, slashes his own arm and taunts Nezuko with his blood, trying to get her to show her true colors as a demon.

It’s Valentine’s Day. Zenitsu is full of excitement and unable to calm down revisits an incident from half a year ago.

Zenitsu continues to seek in advice on how to be more popular and approaches teacher Mr. Uzui next.

Flame Hashira Kyojuro Rengoku receives new orders: Travel to the Mugen Train, where over forty people have gone missing, and conduct an investigation. Leaving the Demon Slayer Corps Headquarters, he sets off on this new mission.

The demon that appeared before Tanjiro and Rengoku after they defeated Enmu was the Upper Three, Akaza. While injured and on the ground, Tanjiro is almost attacked by Akaza and narrowly escapes death when Rengoku quickly strikes back. During the intense battle between Rengoku and Akaza, Akaza suggests to Rengoku that he should also become a demon. Rengoku vehemently refuses Akaza's offer, but his injured body is exhausted and being pushed past its physical limits...

Two simultaneous fights continue, Tanjiro, Nezuko and Genya against Hantengu and Tokito against Gyokko. Genya began to show a demonic form. Tanjiro asks him to look for Hantengu's real body, but memories of the past begin to plague Genya.

The Hashira, Sanemi and Iguro, along with their comrades head to an abandoned castle on top of a mountain for a mission, while Tanjiro is being treated at the Butterfly Mansion for the wounds he suffered at the Swordsmith Village. Later on, the Hashira gather at the Ubuyashiki Mansion to hold a Hashira meeting, where Muichiro reveals how the marks manifested. In an effort to strengthen the entire Demon Slayer Corps from the bottom up, the Hashira Training begins...

After talking with Tanjiro, Giyu is able to overcome his past self and decides to join the training. Meanwhile, Tanjiro's wounds have healed enough to join the training, and heads to his first training with the former Hashira, Uzui.

After completing training with Uzui, Tanjiro visits the Tokito residence next. The Demon Slayer swordsmen who have already started the training are dispirited by Muichiro's intense training and harsh words. Tanjiro hears the swordsmen discussing if there's anything they can do about it...

After completing Mitsuri's training, Tanjiro heads to train with Iguro. When he arrives at the training site, Iguro is waiting for him, visibly angry. Will he be able to complete this horrifying training where he'll have to fix his sword skills?

Tanjiro was struggling with Himejima's tasks. Now he finally manages to move the boulder after receiving advice from Genya, whom he meets by chance. With this breakthrough, will Tanjiro be able to overcome Himejima's rigorous training?

During a silent night when the moon shines, Kagaya finally meets Muzan Kibutsuji, who appears at the Ubuyashiki Mansion.