Set Your Heart Ablaze

The thirty-third anime episode, the seventh of season two, concludes the clash between Upper Rank Three and the Flame Hashira. Although Rengoku lands repeated blows, Akaza heals each one instantly, and the Hashira's mortal wounds cannot mend. Rengoku draws on an esoteric technique for one decisive push, determined that no one present will die before the night ends.

After his Flame Tiger is broken by Akaza's Disorder, Rengoku stands wreathed in fire and declares he will protect everyone, unleashing the Flame Breathing Esoteric Art. He drives the Ninth Form against Akaza's Annihilation Type, slashing the demon's arm and chest, but Akaza punches clean through his solar plexus. As the killing wound takes hold, Rengoku recalls his mother Ruka telling him that the strong exist to shield the weak.

Summoning his remaining strength, Rengoku buries his blade in Akaza's neck and holds him fast as dawn approaches. Inosuke and then Tanjiro try to join the fight, but Akaza tears free, stomps the ground to scatter them, and flees toward the trees to escape the rising sun. Tanjiro hurls his sword into the retreating demon and condemns him as a coward, while Akaza insists he is only running from sunlight and that Rengoku will soon die anyway.

Tanjiro proclaims Rengoku the true victor for protecting everyone and never yielding, breaking down in tears. In his final moments Rengoku passes messages to his father and younger brother, accepts Nezuko as a true member of the Corps, urges the boys to set their hearts ablaze, and tells them he believes they will become the next Hashira. He dies smiling as a vision of his mother assures him he has made her proud. Word of his death and Akaza's appearance then spreads to the Hashira and to Kagaya Ubuyashiki, who is told that not one of the two hundred passengers perished.

The first eyecatcher recreates an extra sketch from the eighth volume, while the second mirrors that volume's title page. In the manga the collision between the Ninth Form and Annihilation Type is hidden inside a large explosion, but the anime shows Rengoku cutting through Akaza's arm and chest during the clash. Inosuke leaps into the air to strike in the adaptation, whereas the manga only has him charge forward. The episode's ending theme is the song Homura by LiSA.