
Quick answer — Sachiko Nagai voices Seiichi Yukimura in Tennis no Ouji-sama: Zenkoku Taikai-hen Final, Miyako Miyamori in Umi Monogatari.
Sachiko Nagai voices Seiichi Yukimura (Tennis no Ouji-sama: Zenkoku Taikai-hen Final), Miyako Miyamori (Umi Monogatari).
Seiichi Yukimura is voiced in Japanese by Sachiko Nagai.