Bisuke

is a ninken and a personal summon of Kakashi Hatake.

Background
In the anime, after they made a contract with Kakashi, Bisuke and the other ninken aided him to search the abducted Rin Nohara by the Kirigakure shinobi and acted as a diversion in order to allow them to flee. They also helped searching for the fleeing Orochimaru.

Appearance
He has tan-coloured fur with brown highlights on his long ears and legs. He has the kanji for in the middle of his forehead and has dark, circular markings around his eyes. He wears the standard outfit of Kakashi's ninken which consists of a blue vest with the henohenomoheji seal and a Konoha forehead protector around his neck.

Abilities
Bisuke possesses heightened senses with which he can use to track his target with ease. He has also demonstrated the ability to track his target underground through the use of the Summoning: Earth Release: Tracking Fang Technique as well as hold a target down, allowing Kakashi to attack them freely. He also has has exceptional teamwork with the rest of his pack, able to develop and effectively use several offensive and defensive formations in battle which make use of their manoeuvrability and powerful limbs.

Prologue — Land of Waves
Kakashi called on Bisuke and the ninken pack to track and capture Zabuza Momochi. They managed to bite onto the missing-nin and pin him in place. This allowed Kakashi to use Lightning Cutter without fear of a counter attack.

Sasuke Recovery Mission
A short time later, Bisuke and his fellow ninken would be called upon by Kakashi to track down Naruto Uzumaki and his team who had gone off in pursuit of Sasuke Uchiha.

Sunagakure Support Mission
In the anime, he along with the other ninken were summoned by Kakashi to investigate the Takumi Village.

Kazekage Rescue Mission
Bisuke and the ninken pack were called upon to track down the Akatsuki member Sasori using a small piece of his clothing.

Three-Tails' Appearance
In the anime, he is summoned by himself (since Pakkun was busy) to find Naruto, who had gone after Yūkimaru.

Itachi Pursuit Mission
During the hunt for Itachi Uchiha, Bisuke and Shiba are partnered with Sakura Haruno.

Five Kage Summit
In the anime, Bisuke was seen along with Urushi, Shiba, Akino and Ūhei being deployed by Kakashi each carrying scrolls with intel for the other hidden villages.

Kakashi Hiden: Lightning in the Icy Sky
Kakashi summons Bisuke and the other ninken to search for the exploding tags planted around the Tobishachimaru. Once they gather all the tags, the ninken give them to Might Guy.

Trivia

 * doesn't directly mean "biscuit", which is in Japanese. "Bisuke" is actually the Japanese word for bisque.