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The popular anime voice actor Yoshitsugu Matsuoka voices the character of Sieg, the protagonist of "Fate/Apocrypha." Matsuoka is known for his distinct voice and has portrayed various notable characters, including Kirito from "Sword Art Online," Yuma Kuga from "World Trigger," and Inosuke Hashibira from "Demon Slayer: Kimetsu no Yaiba."