Yuni Kuroba (Japanese: 黒羽祐仁, Kuroba Yuni) is a first-year student at Seiin High School. He is a member of the boys' volleyball team, and serves as an outside hitter and their ace
Kuroba has shaggy black hair and golden yellow eyes. In middle school, he stood at 175 cm (5'7") but grew to 184 cm (6'0") by the time he entered high school.
During matches, Kuroba wears his volleyball uniform – a navy blue jersey with sky blue and white stripes on the sleeves and corresponding navy blue shorts. His position number, 7, and the name of the school are printed on the front of his jersey in sky blue text with a white outline. On the court, he wears white volleyball shoes with black accents, and no kneepads.
- His given name Yuni means "help (divine help)" (祐)(yu) and "benevolence" (仁)(ni).
- His surname Kuroba means "black" (黒)(kuro) and "feather", "wing" (羽)(ba).