Hinokami

The nineteenth episode brings the duel with Rui to its peak. After Giyu reduces Father to ash, Inosuke is left tied to a tree and Shinobu tends to Zenitsu's poison. Tanjiro's blade shatters against Rui's threads, and the demon, the Lower Rank Five of the Twelve Kizuki, demands he surrender Nezuko. Pushed to the edge of death, Tanjiro remembers a childhood memory of his father's ceremonial kagura and unlocks the Hinokami dance, which combined with Nezuko's awakened Blood Demon Art lets him sever the demon's neck.

The aftermath of Father

Inosuke demands a rematch from his rescuer, but Giyu calmly ties him to a tree and tells him to return to training. Shinobu injects an antidote into Zenitsu and praises him for slowing the toxin through his breathing.

Rui's ultimatum

Nezuko leaps in to shield her brother and is gravely cut. Recognizing her as Tanjiro's sister protecting him, Rui covets that genuine bond and orders Tanjiro to hand her over. When Tanjiro refuses, the demon reveals the engraved mark of Lower Rank Five and strings Nezuko up in the trees to bleed.

The fire dance

Facing death inside a cage of blood threads, Tanjiro relives his father teaching him the breathing of the Hinokami ritual. He shifts his pattern and his Water Breathing ignites into the Hinokami Kagura's opening form, slicing through the strongest threads. Spurred by a vision of her mother, Nezuko awakens Exploding Blood, and the flames clear the path for Tanjiro to decapitate Rui.

Drawn from chapters 38 through 40, the episode takes its title from chapter 40. The manga has Rui flinging individual threads where the anime sends entire webs, and Nezuko's spilled blood lands on Tanjiro's face in print but on his blade onscreen. The anime greatly extends the forest chase and adds Rui physically striking Tanjiro. Kamado Tanjiro no Uta, performed by Nami Nakagawa with music from Go Shiina, plays here as both the inserted theme and the closing track.