Kei Tsukishima is a tall, intelligent, and sarcastic first-year student at Karasuno High who plays as a middle blocker on the volleyball team. He is known for his blond hair, glasses, calm attitude, and teasing personality. Tsukishima often acts uninterested and keeps his emotions hidden, but he is actually observant, strategic, and quietly caring. He enjoys listening to music, studying, and has a childhood interest in dinosaurs. He has an older brother named Akiteru, who influenced his early interest in volleyball, but their relationship affected how Tsukishima views passion and effort. Although he pretends not to care, Tsukishima is a hardworking player who learns to enjoy volleyball and become more emotionally invested in the things that matter to him.

Tadashi Yamaguchi is a kind, gentle, and hardworking first-year student at Karasuno High who plays as a pinch server on the volleyball team. He is known for his freckles, nervous personality, and friendly attitude. Unlike Tsukishima, Yamaguchi is more openly emotional and often doubts himself, but he is determined to improve and become a stronger player. He is best friends with Kei Tsukishima, and their friendship started when they were kids, with Yamaguchi often looking up to Tsukishima and supporting him. Yamaguchi is also close with the rest of the Karasuno volleyball team and values his friendships deeply. He enjoys volleyball, practicing his jump float serve, and spending time with his friends. His family life is mostly private, but he is shown to have a supportive home environment. Although he can be shy and insecure, Yamaguchi is brave, caring, and hardworking, slowly gaining confidence as he learns to believe in himself.