
Quick answer — Masahito Kawanago voices Gaston in Berserk, Yukihito Yashiro in Skip Beat!, Tetsuo Nemoto in Gantz: Second Stage.
Masahito Kawanago voices Gaston (Berserk), Yukihito Yashiro (Skip Beat!), Tetsuo Nemoto (Gantz: Second Stage).
Gaston is voiced in Japanese by Masahito Kawanago.