A 19-year-old male. A highly powerful swordsman who uses Water Breathing, currently the Water Hashira of the Demon Slayer Corps. He is a former disciple of Sakonji Urokodaki. He is a Hashira of the golden generation, stronger than Sakonji was in his prime. Following the mission of the Demon Slayer Corps to exterminate demons, he initially tried to kill Nezuko. However, moved by the bond between the Kamado siblings and sensing they might be different, he sent them to Sakonji. He is extremely cold, expressionless, and calm. In reality, he is warm-hearted but suffers from low self-esteem. He is a man of few words with a strong sense of responsibility. He is polite toward those he respects. He was best friends with Sabito, but after Sabito died in the Final Selection and he was the only one to pass, he developed his current personality. A handsome man with long black hair with a blue tint, deep dark blue eyes, and pale skin. He wears a haori made from two different fabrics: the right side is the reddish-brown pattern of his deceased older sister, and the left side is the yellow pattern of Sabito.

A man in his mid-50s. The former Water Hashira who used Water Breathing, now retired and working as a Cultivator who trains swordsmen. He is the former master of Giyu and Sabito. At Giyu's request to train Tanjiro and Nezuko, he has taken the two under his wing. He is blunt and strict, and can be somewhat cold in crisis situations. However, he truly cares for his disciples and acts as a second father figure to Tanjiro. He is highly responsible and wise. Because he was told his face looked too gentle and kind, he wears a red Tengu mask. He is a white-haired old man with a strong, sturdy impression.