Toki

is the daughter of the late daimyō Ōwashi, twin sister of Sagi, and the ruler of the Land of Birds.

Background
She lost all hope after her brother died, and nearly committed suicide, but Sagi's spirit stopped her, and gave her his stopped pocket watch, symbolizing her inability to move past the loss.

Land of Birds Arc
She posed as her brother Sagi as the daimyō, and assumed the identity as the Cursed Warrior in order to kill Hōki (disguised as the priest Mōsō), the person who had assassinated her brother and father. Toki attempted to attack Hōki, but was defeated, and resigned herself to death, seeing that she was unable to take revenge. Naruto, however, arrived and convinced her to live on for the sake of the Land of Birds before defeating Hōki. After Hōki's defeat, Toki's watch began moving forward again, symbolizing her ability to move on. The next day, Toki revealed her deception and apologized to the people of the land, but asked to be allowed to continue ruling the land to help restore it to its peaceful nature. The people forgave her and she continued to rule as Toki.

Trivia

 * Her character is very similar to Koyuki Kazahana and Haruna. All three of them are daimyō, were in disguise, their fathers were assassinated, and endured a tragedy that which made them act cold towards other people until meeting Naruto. All three seemed to grow fond of him as well.
 * "Toki" means "time".

Quotes

 * (To her brother after receiving his stopped pocket watch) "I will definitely avenge you in order to make your frozen time move again."