The story arc of the red light district of demon slayer 2 introduced the demons Gyutaro and Daki, who form the sixth crescent moon. At first, Tanjiro only reveals himself to Daki, and with the lace ribbons of his kimono he manages to get the young demon slayer into serious trouble, who is rescued by his sister Nezuko.
Then Tengen Uzui rushes to their aid, the he defeats Daki with disarming ease. Here, however, that in Demon Slayer 2x14 emerges from the demon's body Gyutaro, the stronger half of the Sixth Crescent. He's endowed with an incredible ability: he actually can check his blood and hurl it at the opponent in the form of sharp blades. Gyutaro can also give parts of his body to his sister to ensure he is always with her. The parallelism with Tanjiro and Nezuko is obvious, and in Demon Slayer 2x17 Gyutaro will face the young demon slayer relationship with sister.
The two halves of Sixth Crescent, over the course of the last episodes they have led to incredible fights. Gyutaro cut off Tengen Uzui's hand while Daki alone was able to withstand Tanjiro, Inosuke and Zenitsu. To defeat them permanently, the protagonists had to cut off the demons' heads at the same time. This is the only way to avert the double threat of the sixth crescent moon.
Zenitsu and Inosuke took care of Daki's head in Demon Slayer 2x17 while Tanjiro and Uzui teamed up to defeat Gyutaro but reported back multiple wounds. We don't know what their fate will be in the next few episodes, but the Sixth Crescent Brothers' demonic abilities perfectly matched the animations of Ufotable's Studio, which gave us epic and exciting battles. Who knows in what other ways they will amaze us in the coming seasons...