No Matter How Many Lives

The eighteenth and final episode of season two, adapting chapters 95 through 97, opens as Gyutaro's dying body erupts and Nezuko emerges to burn the blood blades away, saving everyone. Her flames then purge the poison from Inosuke and from Tengen, both near death. Tanjiro collects an inert sample of Gyutaro's blood for Tamayo before overhearing the two demons bicker as they begin to disintegrate, Daki cruelly disowning her brother.

The siblings' past

Tanjiro intervenes, urging the pair not to curse each other in their final moments. A flashback reveals Gyutaro's brutal childhood in the lowest district, his devotion to his beautiful sister Ume, and the burning that nearly killed her. The former Upper Six, a wandering demon, offered them his blood and transformed them both.

Aftermath

In a misty afterlife, Ume refuses to leave Gyutaro, and the two walk into the flames together. Obanai Iguro arrives and presses Tengen, who announces his retirement. A crow reports the victory, delighting an ailing Kagaya, while Akaza is summoned to the Infinity Castle, realizing an Upper Rank has fallen.

The episode is named after chapters 96 and 97 and runs about 32 minutes with no intermission eyecatchers. Her use of those flames to incinerate Gyutaro's last barrage of blades does not occur in the manga. The episode also corrects a mistranslated line from chapter 96 that had stated Gyutaro was thirteen when Ume was born, rather than Ume herself.