Kokuou

Kokuō (穆王, Kokuō), more commonly known as the Five-Tails (五尾, Gobi), is a tailed beast sealed within Han from Iwagakure. It has been captured, extracted, and sealed by Akatsuki. In the anime, Kokuō is indicated to have been one of the two tailed beasts that Akatsuki captured before the start of Part II.