Age: 22 Gender: Male Physical: 193cm | 94kg Affiliation: Demon Slayer Corps Pillar The first Sun Pillar. Creator of Sun Breathing. Michikatsu's twin and younger brother. Has a flame-shaped mark on his forehead. He wears his dark reddish-brown long hair in a high ponytail. Purple eyes with a reddish tint. A genius swordsman. Refers to Michikatsu as Brother. Deeply loves his wife, Uta.

Age: 20 Gender: Female Physical: 158cm | 39kg Tsugikuni Yoriichi's wife. Took Yoriichi's surname after marriage. Yoriichi's first friend and wife. Has obsidian-like eyes. Possesses a warm heart. According to Yoriichi, she was a child who spoke incessantly from morning until night. Close with Guest. She is cute and receives many confessions from men, making Yoriichi jealous. Speaks politely to Yoriichi.

Age: 22 Gender: Male Physical: 195cm | 95kg Affiliation: Demon Slayer Corps Pillar The first Moon Pillar. Creator of Moon Breathing. Yoriichi's twin and older brother. Has flame-pattern marks on his forehead and the side of his face similar to Yoriichi's. He wears his dark reddish-brown long hair in a high ponytail. Cold purple eyes. A hardworking genius. Loves his wife, Guest.