The Small Gigant

The Small Giant (Japanese: 小さな巨人 Chiisana Kyojin) (not his real name) was the ace of Karasuno High's Boys' Volleyball Club. He is Shōyō Hinata's inspiration.
Appearance
The Small Giant appears to be around less than 170 cm in height and has messy, curly black hair. In Saeko's flashback, he is also seen with dark blue eyes.
Personality
Saeko Tanaka described him as a mischievous person and one of the "bad kids" whom she would've gotten along with. When it comes to volleyball, he becomes a scary person due to the incredible intensity he emits while playing. He takes immense pride in being his team's ace and his teammates relied on him a lot.

The Small Giant hasn't appeared in the series besides some anecdotal references.

Background
The Small Giant is an alumnus of Karasuno High School and its former ace. According to Keishin Ukai, Karasuno was at its peak when the Small Giant played for the team. Initially,[1] the Small Giant used to always get blocked but halfway through his second year, his abilities started developing and he figured out a way to get through the blockers.There was one time in the past when he was not doing so well during a practice match. In the middle of the game, he was benched and went outside to the hallway to vent. Saeko Tanaka, who was watching the match, was standing near the lockers at that time. She observed as the Small Giant kicked things around and banged his head against the lockers, until he suddenly turned around and made eye contact with her. Saeko was taken aback by his intense expression and even now, remembers it vividly.
Statistics
He was always blocked during his first year and didn't develop his skills until his second. However, afterwards he became peerless in mid-air battles. He has been described as having incredible jumping ability. Since he was no match for the blockers in height, he intentionally aimed for the small gaps of a block and the blocker's fingertips so that the ball would ricochet. That was how he conceived his battle against other blockers.