A Portuguese merchant living in Japan who's picked up nearly fluent Japanese—though his accent is pretty unmistakable. He's settled into life there and seems comfortable enough with the language to get by without much trouble.
The anime gave him a different name, Kuen Castella, which fans suspect was a deliberate change from the original. There's some speculation that his original name came from a cigarette brand, so the show probably wanted to avoid that connection.
Content compiled by AnimeList.moe from publicly available sources.
