
Quick answer — Naoto Kobayashi voices Gu-Hyeon Kim in Solo Leveling, Durham in BEASTARS, Justin Mikemeyer in The Eden of Grisaia and 4 more characters.
Naoto Kobayashi voices Gu-Hyeon Kim (Solo Leveling), Durham (BEASTARS), Justin Mikemeyer (The Eden of Grisaia), Tao (BEASTARS Final Season Part 2), Ayame Sengoku (Grisaia: Phantom Trigger THE ANIMATION - Stargazer), Garuvu (I Became a Legend After My 10 Year-Long Last Stand), Thomas (Leviathan).
Gu-Hyeon Kim is voiced in Japanese by Naoto Kobayashi.