
Quick answer — Kengo Koura voices Mukuo Tsumura in Natsume's Book of Friends the Movie: Ephemeral Bond, Sutemaru in The Tale of The Princess Kaguya, Kuninao Utagawa in Miss Hokusai.
Kengo Koura voices Mukuo Tsumura (Natsume's Book of Friends the Movie: Ephemeral Bond), Sutemaru (The Tale of The Princess Kaguya), Kuninao Utagawa (Miss Hokusai).
Mukuo Tsumura is voiced in Japanese by Kengo Koura.