Nakago is considered to be the leader of the Seiryuu warriors, is the main antagonist of Fushigi Yuugi. His true name is Ayuru Gi, born under the star Heart.
Nakago is both merciless and charismatic; he eliminates those whose usefulness to him is exhausted and skillfully manipulates others into doing as he wishes. Nakago's powers as a Celestial Warrior is shown to be stronger than any of the Suzaku and Seiryū warriors, having the ability to manipulate chi, enabling himself to become psychokinetic, fire energy blasts, and set up force fields. In battle, Nakago also utilizes a whip and sword.
As Kuto's highest ranking general, Nakago commands two thirds of Kuto's army. The last of the Hin Tribe—a people destroyed at the orders of the Emperor of Kuto—Nakago was captured after seeing his mother being raped by Kutō soldiers, triggered his powers and killed the soldiers and his own mother. With the surviving soldiers recognizing him as a Celestial Warrior, Nakago is brought to the Emperor where his natural beauty results in his being sexually abused by the Emperor. As he mastered complete control over his abilities, he eventually became a seemingly loyal soldier of Kuto, with the Emperor unaware that Nakago has been planning to betray him all his life.
Yu Watase notes on several occasions in the chapter notes, as well in the second installment of the omake "The Tale of the Forbidden Women's Hot Spring" from the series 1 OVA (as stated by Nakago himself), that Nakago is her favourite character.
