Voiced by: Natsuki Hanae
A kindhearted boy.
He lived a blissful existence with his mother and siblings, but were attacked by demons while he was out working.
He joins the Demon Slayer Corps in order to turn his sister Nezuko, who has become a demon, back into a human, as well as to avenge the death of his family by hunting down the demon who killed them.
Under the tutledge of Sakonji Urokodaki, he learns to wield "Water Breathing", so that he can face the demon threat.
Voiced by: Hiro Shimono
He joins the Demon Slayer Corps at the same time as Tanjiro and Inosuke.
He has an acute sense of hearing, and can identify the sounds made by other people or demons.
In battle, when he is scared to death, he falls asleep and his personality changes to the swordsman that can unleash his "Thunder Breathing".