Sumire Ryuzaki

Sumire Ryuzaki (竜崎 スミレ, Ryūzaki Sumire) is the coach of Seigaku's tennis club, as well as one of the school's math teachers. It was thanks to her that Nanjiro Echizen was able to develop his skills. She is the grandmother of Sakuno. She also has a sort-of rivalry with her ex-mentor, Mikiya Banda a.k.a. Banji, who is the coach for Yamabuki. She is always there to yell, but is also considered to be a great and reliable coach. She has a good relationship with her regulars, and participates in their recreational group activities: the bowling reunion and the beach-volley mini-tournament with Rokkaku Middle School. For the Prince of Tennis live action movie, Ryuzaki's whole personality and back story was changed. Instead of being a middle-aged teacher and ex-coach to Nanjiro Echizen, she is a young, and more cheerful woman as well as Nanjiro's former classmate, who was her reason for playing tennis and becoming coach. She was played by the popular singer Hitomi Shimatani. The Chinese drama also makes her a young woman, and in this version she is portrayed by Jiang Hong Bo.Voiced by: Shizuka Okohira (Japanese), Barbara Goodson (English)

Source: Wikipedia