
Quick answer — Shinei Ueki voices Don in The Promised Neverland, Louis Kino in 86 EIGHTY-SIX, Boris Marcus in How NOT to Summon a Demon Lord.
Shinei Ueki voices Don (The Promised Neverland), Louis Kino (86 EIGHTY-SIX), Boris Marcus (How NOT to Summon a Demon Lord).
Don is voiced in Japanese by Shinei Ueki.