Thank You

Akaza rages at Tanjiro and Giyu for forcing his painful past back to the surface, scorning humans as fragile and short-lived. His head regenerates and he launches Destructive Death: Annihilation Type. Tanjiro rises and means to behead him again, his blade kindling with the Hinokami Kagura, but the sword slips from his grip, leaving him to strike Akaza's face with his fist instead.

The punch reminds Akaza of his first meeting with Keizo. He grasps that he has spent his demon existence weaponizing his master's style and betraying his father's final wish, and he realizes who he truly needs to destroy.

Akaza turns on himself

Tanjiro hurls himself and Giyu clear of the incoming Annihilation Type, then notices Akaza smiling as the shockwaves tear his own body apart. The corpse gives off a scent of gratitude. Akaza halts his regeneration and concedes that the fight is lost.

Reunion in spirit

As his ruined form walks away, Akaza's spirit meets his father, who thanks him, and Keizo, who promises they will never abandon him. Muzan urges him to keep fighting, and his body briefly regenerates, but Koyuki's spirit touches his face and tells him he has done enough.

Overcoming Muzan's hold, Akaza grasps Koyuki's spirit as the human Hakuji once more, weeping as he apologizes for failing her. With her welcome home, he stops his regeneration for good. Tanjiro watches the body of Upper Rank Three crumble into ash.