Hi Kimichika Haijima (Japanese: 灰島公誓, Haijima Kimichika) is a first-year student at Seiin High School. He serves as a setter for the boys' volleyball club, and is referred to as the "Genius Setter" due to his remarkable skills.
Haijima has short blonde hair and blue eyes. He has worn glasses since kindergarten, but swaps them out for contact lenses whenever he's practicing or playing. He has been seen to tape his fingers as well. In junior high, he stood at 172.7 cm (5'8”), but grew to 181 cm (5'11") upon entering high school.
During matches, Haijima 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, 8, and the name of the school are printed on the front of his jersey in sky blue text. On the court, he wears white kneepads, a white elbow pad on his left arm and white volleyball shoes with black accents.
During practices, Haijima wears a black long sleeve shirt, grey gym shorts with white stripes on the side and black leggings, as well as his volleyball shoes. Outside of matches, he is most frequently seen in his school uniform or volleyball tracksuit.
Kimichika often comes off as cold and emotionally distant, but has shown a softer side around people he cares about, such as Yuni Kuroba. He shows a great love for volleyball, and is incredibly driven, focused and determined to bring any team he plays on to victory. However, the brutal honesty he uses when critiquing his teammates and his short temper that flares whenever he is frustrated has caused tension with other players throughout the years. Despite this tension, and the incidents that were caused because of it, Kimichika has stated that he doesn't regret the things he says.
Until kindergarten, Kimichika lived with his parents in Suzumu City, Fukui Prefecture, which was next to the town of Monshiro. Because his mother was in and out of the hospital due to her illness, he was often left at his maternal grandparents' house in Monshiro. His grandfather used to bring him to Yuni Kuroba's grandfather's house to play shogi, and the two boys became friends from there. After his mother's death, his father took him to live in Tokyo. In middle school, he attended the volleyball powerhouse school, Meisei Academy.
- He is known as the other genius in Fukui Prefecture, alongside Subaru Mimura.
- Kimichika has been wearing glasses since kindergarten.
- Kimichika made himself ambidextrous so he could emulate a player he likes, Abe who was chosen for the national team. 
- His given name Kimichika means "king", "lord", "prince", "ruler" (公, which is an alternate form of 君) (kimi) and "oath", "vow" (誓) (chikai)
- His surname Haijima means "ash" (灰 ) (hai) and "island" (島) (jima/shima)
- Book 1 Chapter 1.2 SECOND TOUCH
- Book 1 Chapter 1.1 FIRST TOUCH
- Season 1 Episode 1