Nihon Country, or Japan (日本国) in Tsubasa RESERVoir CHRoNiCLE, is the home country of Kurogane, Princess Tomoyo, and Empress Amaterasu (アマテラス). It resembles feudal-era Japan, both in architecture and in class structure. Amaterasu rules over the court/land and is protected by ninja guards, which includes Sōma and Kurogane. "Japan" is filled with samurai and many warriors. It is a nation torn by nothing but wars.