Guruko

Guruko receives little individual dialogue, with most of his characterization coming through his role among Kakashi's ninken. He is obedient, dependable, and willing to enter dangerous situations when summoned.

He functions naturally as part of a group rather than seeking independent action. The ninken understand one another's movements well enough to surround, track, and immobilize shinobi while giving Kakashi an opening to attack.

Guruko possesses the heightened sense of smell characteristic of Kakashi's ninken and can track targets over long distances. When summoned through Summoning: Earth Release: Tracking Fang Technique, he and the other dogs can pursue a target underground before emerging and biting onto the opponent to immobilize them.

Anime material expands the pack's coordinated combat abilities with techniques such as Crane Wing Formation, Dog Wall Formation, Circular Formation, and Ninken Ninja Art: Dance of the Dust Cloud. These techniques rely on the dogs' agility, powerful limbs, and highly developed teamwork.

Although individually small, Guruko becomes dangerous when operating with the entire pack because their attacks are designed to deny opponents room to evade.

Guruko first appears during the Land of Waves mission when Kakashi summons his ninken to locate Zabuza Momochi. After tracking Zabuza through the ground, the dogs emerge and restrain him by biting onto his limbs, allowing Kakashi to prepare Lightning Cutter without risking an immediate counterattack.

Kakashi later summons the pack during the pursuit of Sasuke Uchiha, using their tracking abilities to follow the shinobi involved in the Sasuke Recovery Mission.

Anime flashbacks expand Guruko's history by depicting Kakashi's ninken helping search for Rin Nohara and later participating in operations connected to Orochimaru.

Kakashi Hatake is Guruko's summoner and the shinobi whose commands the ninken pack follows.

Pakkun is the most prominent and frequently speaking member of Kakashi's ninken.

Bisuke, Akino, Shiba, Uuhei, Urushi, and Bull are Guruko's fellow members of Kakashi's ninken pack.

Zabuza Momochi is one of the enemies Guruko helps track and immobilize.