(Japanese: 月島つきしま 蛍けい, Tsukishima Kei) is a first-year at Karasuno High. He plays as one of the starting middle blockers on the boys' volleyball teamTsukishima is very tall and has an incredibly slim build for a volleyball player. Despite being a first-year, he is the tallest player on the volleyball team; standing at 190.1 cm. He has short blond hair, pale skin, thin eyebrows, and golden-brown eyes. He is often seen with a frown or a condescending smirk on his face. After joining the Karasuno volleyball team, Tsukishima wears the standard Karasuno volleyball uniform (black, orange, and white uniform with the number 11 on the back) during matches. He also wears knee pads and white volleyball shoes with green details. He is also the only player on the Karasuno team who wears glasses.Tsukishima is very blunt and will sometimes rile his teammates up due to his antagonistic nature (most notably being Hinata, Kageyama, Nishinoya, and Tanaka) and sometimes other teams because of his casual smug attitude, taking pride in and relishing when his opponents see him as a nuisanceDespite coming across as arrogant, Tsukishima has low self-esteem and thinks of himself as inferior to others in certain areas. This is first noted to be a surprise by Kuroo, who accidentally riles him up by suggesting he'll lose to Hinata, to which he says that he's already below him. After the Shiratorizawa match, despite being the MVP, he's seen calling himself lame for only being able to block Ushijima's spikes once, only adding to how little he believes in himself and his achievements. While he willingly admits his own faults, he does not like it when others point these things out, becoming annoyed and angry when Hinata tried to take responsibility in blocking Ushijima and then when Bokuto called his blocks weak in a sense of strength given how easily he got by him during practice. Knowing his limitations, Tsukishima reluctantly knows he must depend on others for certain things and gives his own version of motivation that is usually disguised as jabs at their skills or pride.

(Japanese: 山口やまぐち 忠ただし, Yamaguchi Tadashi) was a first-year student at Karasuno High. He was a middle blocker and pinch server for the Boys' Volleyball Team. During his third-year, he became the team captain.He has dark grayish-green hair with a flyaway piece of hair sticking up at the top. He has large eyes with small, amber colored pupils. Yamaguchi is taller than average and has a thin build. This, coupled with his freckles, had caused him to be bullied when he was younger,[3] although he doesn't seem to be bothered by this anymore. After joining the Karasuno volleyball team during games, Yamaguchi wears Karasuno's black, orange, and white uniform with the number 12 on the back. He also wears knee pads and white volleyball shoes with black accents.Yamaguchi is a pretty shy person who relies on others early on, most likely stemmed from being bullied because of his appearance. Despite this, Yamaguchi is generally a nice person but does tend to join Tsukishima in teasing others, mainly Kageyama and Hinata. He does show that he is a loyal friend and a supportive teammate. Yamaguchi can at times be seen defending Tsukishima from things he believes were insults toward his friend.Originally, Yamaguchi constantly doubted his abilities and had difficulty handling his nerves. It was through hard work and seeking mentorship through Shimada that he was able to better his skills and become more confident. By the time Karasuno had their rematch against Aoba Johsai in the semifinals, Yamaguchi has made exceptional progress in both his gameplay and emotions.Back in elementary school, Yamaguchi was teased for his freckles and overall scrawniness. Once Tsukishima unintentionally saved him from some boys who bullied him by calling them pathetic. Despite thinking that he was included among the ones Tsukishima insulted, Yamaguchi still grew attached to him and looked up to him, he set his goal to become "as cool as him". He is later revealed to want to join a sports club to become stronger but decided against soccer and basketball because the other players were 'big and scary' and volleyball seemed the safer choice. From this, he and Tsukishima grew to become close friends.