The Curse

With Yahaba beheaded, Tanjiro reflects that his Whirlpool form gained extra force by riding the demon's own arrows. The dying Arrow Demon spits curses and summons new arrows inside Tanjiro's body, hurling him about the chamber. To avoid being torn apart, Tanjiro chains one Water Breathing technique after another, more forms back to back than he has ever managed, until the arrows finally fade and let him go.

He touches down using the Sixth Form, yet the damage is severe, a broken leg and several fractured ribs. Wincing through the pain, he clamps the sword between his teeth and hauls himself along the ground toward the others, silently hoping that Tamayo, Yushiro, and Nezuko remain unharmed.

Close by, Nezuko boots Susamaru's temari ball straight back, and the pair exchange ever harder, faster kicks until the Temari Demon herself is forced to dodge. Yushiro wonders aloud whether Tamayo's medicine raised Nezuko's strength, but Tamayo clarifies that it merely quickened her healing, so this power belongs to Nezuko alone, gained without eating any humans.

Tamayo then steps forward and goads Susamaru, branding Muzan a coward who dreads his own demons uniting to break his grip. Rushing to defend her master, Susamaru blurts out his surname, exactly the slip Tamayo wanted. Her Magical Aroma of Daylight, a spell that compels truth, had loosened the demon's tongue, and saying the name activates the curse. As Susamaru pleads for mercy, her frame contorts and three enormous arms tear out of it.

The chapter wraps up the Asakusa fight against Susamaru and Yahaba, demonstrating Tanjiro's improving ability to chain Water Breathing forms while under extreme strain.

It also expands Muzan's lore, exposing both the curse that destroys any demon who utters his name and Tamayo's spellcasting talents, while reinforcing that Nezuko grows stronger without preying on people. Susamaru's grotesque transformation foreshadows her death and the danger Muzan represents to his own followers.