Nezu is a scholarship student in the Advanced Class at the Morinomiya Academy with Inomata Maria and is best friends with Yagi Tomoya, who also refers to him as "Chuukichi". He is the second son out of six children.
Nezu is tall and slender. He has black, unkempt hair that sticks up at the ends and bangs that cover his dark eyes entirely, though they are shown when he is talking at times. He has a serious and sullen expression, rarely seen with a smile.
Nezu is a calm and reserved teen. He is very practical in his actions, having to care for his many siblings. In addition, he is also studious and hardworking, ending at the top of his class second only to Inomata.
He is serious all the time, retaining a mostly deadpan expression when dealing with problems, such as his siblings breaking into the chairwoman or Ryuuichi's home as they are running away from home, and of course managing Yagi's behavior around the children. He also displays a polite manner and etiquette in social situations like a proper adult.
Nezu is the second eldest son of six children. He has one older brother, Daikichi, three younger brothers, Shoukichi and the twins, Kichi and Suekichi, and only one younger sister, Kyouko. He comes from a poor family and these special circumstances led him to work multiple part-time jobs, something which is uncommon with the other peers at the school. He shows kindness to Yagi in his childhood, who reciprocates by sharing his toys and games in return for companionship. It was once revealed that Nezu would rather create something he wants himself, instead of buying it. (due to tight budget). His siblings thus respect him as an older brother due to his sacrifices as a result.
- Nezu comes from "nezumi", meaning "mouse"
- Lately, he's gotten into the habit of folding the ends of the toilet paper (A habit he is guilty of doing even at his part time job)