Red Sea

Red Sea (赤海, Sekikai) is located south of the Yellow Sea. It borders the three kingdoms of Kou, Sai, and Sou.
 * Kou - The Kingdom of Kou is the first kingdom that Youko Nakajima sets foot in and is one of the four "middle" kingdoms. It was formerly ruled by the unnamed King of Kou.
 * Sou - The Kingdom of Sou is the southernmost kingdom of the Twelve Kingdoms. It is currently ruled by Senshin, whose 600-year reign is longest of the current rulers of the Twelve Kingdoms.
 * Sai- The Kingdom of Sai is one of the four "middle" kingdoms the Twelve Kingdoms. It is currently ruled by Kouko.