Nerugui

Nerugui is a ferret coated in tan fur with red eyes and a black nose. Black colors his face, the fur behind his ears, and each of his feet and lower legs, and four whiskers fan out with two to a side. A small diamond-shaped patch of tan sits in the middle of his forehead.

By Kahiko's account Nerugui is a shy creature who does not lash out at people, which made his behavior toward Naruto all the more surprising. Visibly stung when Naruto mocked him for tumbling into their trap, the ferret struck back and attacked. His loyalty runs to Kahiko's clan, and he generally has little use for anyone outside its royal line.

Nerugui can latch his claws onto a person's face and rake at them, and he is notably quick and nimble. Naruto, Sakura, and Shikamaru were first sent to find him, but capturing him and hauling him back to Kahiko proved difficult, worsened by Naruto's clumsiness and by an ambush from Haido's knights, Temujin among them. After Naruto and Temujin plunged off a cliff during their clash, Nerugui was returned to Kahiko's clan, though he chose to stay near Temujin rather than his old master.

He later turned on Haido and was struck down, the blow forcing him to cough up the Stone of Gelel fragment that had been holding back his aging. In the end he departed with Temujin for the new land.