
Quick answer — Mitsuaki Kanuka voices Guen in The Apothecary Diaries, Masashi Kawata in THE FIRST SLAM DUNK, Nakata in Girls Band Cry and 14 more characters.
Mitsuaki Kanuka voices Guen (The Apothecary Diaries), Masashi Kawata (THE FIRST SLAM DUNK), Nakata (Girls Band Cry), Fen (To Your Eternity Season 2), Loccobarocco (JoJo's Bizarre Adventure: STONE OCEAN), Mukasa (Terror in Resonance), Mark (Clevatess), Death Oji A (ZOMBIE LAND SAGA) and 9 more.
Guen is voiced in Japanese by Mitsuaki Kanuka.