Tamahiko Teshiro is a first-year student at Nekoma High and the youngest member of the school's volleyball team, playing as a setter and pinch server with jersey number 9. He has a relatively small stature, short light-colored hair, and matching thick eyebrows, typically maintaining a composed expression. After the timeskip, his hair grows out slightly. Teshiro remains calm and collected under pressure, demonstrating perceptiveness by noticing shifts in his teammates' behavior during critical moments. However, his inexperience leaves him vulnerable to decoy tactics and imperfect receives. He first appears on the sidelines during the Spring High Preliminary matches against Fukurōdani and Nohebi Academies. His initial opportunity to play comes in the Tokyo Nationals match against Sarukawa Technical High, though Nekoma secures victory before he can be substituted in. Teshiro finally enters a match during the second set against Karasuno High when the score is tied. Despite admitting he does not feel fully ready, he delivers a disruptive ceiling serve that stuns everyone and breaks Karasuno's rhythm. He struggles with powerful spikes and feels overwhelmed by the match's intensity. Following the loss, he expresses a strong desire to compete in more high-caliber games. Proficient in the ceiling serve, Teshiro uses it to disrupt opponents, though his receiving skills lag behind those of his more experienced teammates. His level-headedness is a noted strength. He gets along well with his teammates, particularly the other first-year players, and is supportive within the team dynamic. After high school, Teshiro becomes a cram school instructor as of 2021. He later reunites with former teammates at a gathering at Kenma Kozume's house. His favorite food is grilled salted cod, and he is sometimes asked if he is angry. His surname, Teshiro, can mean "white hand," while his given name, Tamahiko, can be interpreted as "ball boy." In the OVA "Land VS Air," Teshiro is present during Nekoma's matches but has limited on-court involvement.