
Quick answer — Yasuhiko Kawazu voices Itani in Colorful, Seiji Tsukishima in Cross Game, Corin Nander in Turn A Gundam and 8 more characters.
Yasuhiko Kawazu voices Itani (Colorful), Seiji Tsukishima (Cross Game), Corin Nander (Turn A Gundam), Kaio Yo (Baki: The Great Raitai Tournament Saga), Bar Saitou no Master (Bartender), Souchirou Suzumiya (Rumbling Hearts), Ryuukongou (Grappler Baki: The Ultimate Fighter), Glide.EXE (MegaMan NT Warrior) and 3 more.
Itani is voiced in Japanese by Yasuhiko Kawazu.