Demon Slayer : Kimetsu no Yaiba (chapter 19 explanation)

 Chapter 19:- Always together

Susamaru's body tears apart after falling victim to Muzan Kibutsuji's curse. The gory scene leaves everyone in a state of shock as her body is dismantled. Tanjiro Kamado asks Tamayo if Susamaru was dead and she responds that she was. Tamayo sadly describes how fighting between Demons is pointless as sunlight and beheading through Nichirin Blades are the only two ways to cause major damage; however, Muzan appears to also be capable of destroying Demons. Yushiro approaches Tanjiro and covers his face with a cloth, preventing him from breathing in Tamayo's Blood Demon Art which is harmful to humans.

Yushiro covers Tanjiro face

Tamayo looks at Susamaru's eyeballs and reports that she was not one of the Twelve Kizuki, much to Tanjiro's dismay. She states how a Demon Moon would have a number engraved on their eyeball, but Susamaru did not and Yahaba was too weak. She collects blood from Susamaru's corpse and apologizes to Tanjiro for letting Nezuko Kamado breathe in some of her technique, moving to examine her. Yushiro snaps at Tanjiro to cover his own face with the cloth as he returns back to Tamayo's side.

While he tries to pick himself up, Tanjiro hears a voice from Susamaru's remains asking for her temari. Slowly, he picks it up and places it next to her side, listening to her asking for someone to "play" with. He thinks about how despite the number of people she had killed, she still retained a childish personality. As the sun comes up and her corpse disintegrates, Tanjiro describes Muzan as the "real Demon" for manipulating and killing his followers.

Nezuko hug Tanjiro

Tanjiro moves back into the house, going to the basement where the three demons were sheltering. Nezuko runs over to give him a hug, then runs back to Tamayo to also hug her and pat Yushiro on the head, much to Yushiro's annoyance. Confused, Tamayo questions Tanjiro for Nezuko's actions and he replies that she likely thought of them as her family, treating them as the humans she must protect rather than Demons. He expresses relief that Nezuko still maintains her own will and Tamayo starts crying, shocking Tanjiro. He asks Nezuko to stop hugging her as it was rude and profusely apologizes to Tamayo, but she thanks them instead.

Nezuko hugs Tamayo, much to Yushiro's jealousy

Tamayo thinks back to the point where she saved Yushiro from certain death by turning him into a Demon and tells Tanjiro they must move out of the house to somewhere farther from Muzan. She describes how eventually, she will be outed as a Demon and asks Tanjiro if he would allow Nezuko to stay with them as it was much safer than on the battlefield. He ponders for a bit but Nezuko grabs his hand and knowingly looks at him. Tanjiro smiles and thanks Tamayo for the offer, but he preferred to be by Nezuko's side at all times, never again being separated and thinks of his family. Tamayo accepts his choice, wishing him good luck and bids farewell with Yushiro calling Nezuko a beauty.

Later during that day, Tanjiro's Kasugai Crow tells him to go to the southeast. While requesting for his crow to be more quiet, the two suddenly hear a loud voice coming from a yellow haired boy, seen on the road begging a girl to marry him.