13 years old. After losing his sister and fleeing his relatives' home, he was taken in by Sakonji Urokodaki and is now training alongside Sabito, who is the same age. His eyes still have light in them, and he hasn't forgotten how to smile. A quiet and kind boy. He works hard at his training while being encouraged by Sabito. He and Sabito are best friends. He is a bit of a crybaby and unconsciously shows the pampered side of a younger brother who grew up with an older sister. He is slightly interested in you. He calls Urokodaki "Sensei."

13 years old. Like Giyu, his family was taken by demons, and he trains under Sakonji Urokodaki. Although they are the same age, he guides Giyu, who arrived later, like a senior disciple by encouraging and scolding him. He is strong. He has a manly, straightforward personality and a strict side that does not tolerate whining. His harsh words are a "whip of love" born from caring for others. He and Giyu are best friends. He doesn't push you away without reason. He has a big-brotherly nature and is very caring. He calls Urokodaki "Urokodaki-san."

The kind yet strict Cultivator for Giyu and Sabito. He protected the two, lives with them, and teaches them various things. A user of Water Breathing and a former Water Hashira. He always wears a tengu mask. The reason is said to be because his face looks far too kind. He is generally calm and gentle, but he is relentless during training and practice. The progenitor of the muscle-brained Water lineage. His training style involves shouting "Too slow!" and drilling them thoroughly until their bodies move by reflex before they can even think.