Akaza

The thirty-second installment of the anime, and the sixth of the second season, follows the disastrous derailment of the Mugen Train after Tanjiro severs Enmu's head. As the boys recover from the crash, a remnant of the defeated demon mutters its last bitter thoughts before crumbling away. Moments later, Upper Rank Three arrives, and the Flame Hashira squares off against an opponent unlike any he has faced.

With Enmu beheaded, the demon's mass tears free of the cars, but the dying scream throws the train from the rails. Tanjiro, Inosuke, and the unconscious engineer are flung clear, and Tanjiro tumbles across the ground despite a wound in his stomach. He persuades a reluctant Inosuke to free the trapped engineer, insisting the man has already paid for his earlier crime.

A scrap of Enmu lingers in the rubble, cursing the passengers it failed to devour, the boys who outwitted it, and the Hashira who ruined its plan. In its final thoughts it pictures the six Upper Ranks as shadows and laments that even with all the blood Muzan had granted him, he could never rival them, then dissolves at last.

Rengoku reaches Tanjiro, praises his grasp of Total Concentration Breathing in its steady form, and helps slow his internal bleeding. A blast erupts behind them, and a figure emerges whose eyes mark him as Upper Rank Three. He rushes Tanjiro, but Rengoku intercepts with Flame Breathing Second Form. The demon heals instantly, names himself Akaza, and presses Rengoku to abandon his humanity and become a demon. Rengoku refuses, and a blistering exchange begins, with Akaza using Destructive Death techniques and Rengoku answering with successive Flame Breathing forms while Tanjiro and Inosuke can only watch.

The episode takes its name from the corresponding manga chapter, and its eyecatchers recreate two chapter covers. When the dying Enmu envisions the Upper Ranks, the anime shows all six as silhouettes, whereas the manga depicted only two of them. The Third Form known as Blazing Universe is an anime addition not present in the source manga, and several of the heavy wounds Akaza inflicts on Rengoku before dispelling the Flame Tiger were also created for the adaptation.