Mio Kofune

Mio Kofune is Ushio's younger sister and a first-year high school student. She is good at sports, belongs to the swimming club, and has tanned skin. Despite the death of her older sister, she has a healthy side, such as her cheerful attitude toward Shinpei when he returns home. Mio is a young girl with medium long black hair and blue eyes. She also has a tanned skin.

Mio can be described as a shy yet cheerful girl who is also very protective and kind, willing to do whatever it takes to keep her loved ones safe. She is also shown to be quite bubbly at times, and also harbors feelings for Shinpei Ajiro.