Koi Shūrai (濃い襲雷, Shurai Koi) is a shinobi from Iwagakure and is the great grandson of the Third Tsuchikage. He is also the Jinchuriki of the Four-Tailed Monkey (四尾の猿, Yonbi no Saru). Despite his status as a Jinchuriki he remains loyal to the hidden stone village and is currently serving as a Tokubetsu Jōnin, who specializes in elemental ninjutsu.