Samurai

Kokushibo recalls how Yoriichi's smile always disturbed him, especially when his brother spoke hopefully about the Breathing Styles outliving them. Proud that his own generation was uniquely special, he is sickened by the persistence of the modern Hashira: fighters who keep their blades even when dismembered, who wield Blood Demon Arts while human, who refuse to bleed out, and who grow at a pace rivaling demons. Furious at the thought of losing, he stops the bleeding at his severed neck and vows never to fall, even after decapitation.

Gyomei orders Sanemi to drive the demon into a corner so that Muichiro and Genya's sacrifices are not wasted. The two Hashira strike together as Kokushibo regenerates his head.

Enraged by his brother's faith in the future, Kokushibo regrows his head but takes on a monstrous, unstable form in doing so. Muichiro dies of his wounds. Seeing his hideous reflection in Sanemi's blade triggers a mental collapse and doubt over his own existence. Unable to heal or fight back, he is overwhelmed and destroyed by Sanemi and Gyomei.

The demon hears the voice of a young Yoriichi recalling his wish to be the second strongest samurai in the land, prompting Kokushibo to question whether his current shape is anything he ever wanted. As his body crumbles, he admits in his final thoughts that fear of death may have made him into a man-eating monster, yet what he truly wanted was to be his brother. This Infinity Castle Arc chapter was collected in Volume 20.