Toshiaki is a graduate of Saitoku High School in Tokyo, and he has pitched in Koshien, so he has experience in base running and batting.
Toshiaki noted that something is "missing" in the team, and it is the lack of competition in order to become regulars; which in his oppinion is a bad thing for the team's members.
Toshiaki is a tall man with black, messy hair and apparent eyebrows. He has dark circles under his eyes and a big, easily spotted nose. His choice of clothing usually consists of loose clothes.
He is a strict man that has no qualms for saying the truth in a person's face, or change the lineup so the team would win, regardless of the effect upon said member(s). Even so, Toshiaki is a good man at heart since he decided to help his daughter, Maria, to raise a good pitcher that has not only stamina, but good balance, strength and speed; in combination to revealing the other members' weak points in order to surpass them in due time.
- Toshiaki's occupation is manufacturing machine tools.