Kuromaru

is a ninken from Konohagakure's Inuzuka clan and Tsume Inuzuka's partner.

Appearance
Kuromaru is an adult canine with a wolfish appearance. As his name suggests, he has black fur with a white underside. He is missing his left ear, and wears an eyepatch over his right eye. He appears to have grown much larger in Part II than when he was seen in his brief Part I appearance.

Abilities
As an Inuzuka ninken, Kuromaru uses collaborative attacks alongside his partner Tsume. He is also well versed in the clan's techniques such as the Fang Passing Fang which he used with enough skill to cause extensive damage to the corpse of the first Animal Path during the invasion of Pain.

Out of all the Inuzuka ninken, Kuromaru is the only one that has displayed the ability to talk.

Invasion of Konoha Arc
Kuromaru and Tsume, along with Hana Inuzuka and the Three Haimaru Brothers, assisted in the village's defence during the invasion of Konoha, fending off invading Otogakure and Sunagakure ninja.

Invasion of Pain Arc
During the invasion of Pain, as Pain's Preta Path prepared to dispose of the previous Animal Path, Kuromaru and Tsume Inuzuka found him in one of the morgues. The duo drop a canned flash bomb and attacked it with their Fang Passing Fang technique. The Preta Path however used the corpse of the old Animal Path as a shield and avoided the attack clinging to the roof of the building. As Tsume states that their intel was right on the mark, as this one seemed to dislike physical combat, she and Kuromaru prepares to attack again. Kiba and Akamaru joined them in the battle, and Akamaru marks the Preta Path before escaping through a broken window but Tsume mounts Kuromaru and the two pursue him, but the Preta Path was summoned away before Pain destroyed the village. Kuromaru survived the attack unharmed, and he and his partner were later seen celebrating Naruto's victory over Pain.

Trivia

 * The 'Kuro' in Kuromaru's name means the colour 'black', and 'maru' meaning 'perfection' or 'full circle' is a common suffix for Japanese male names.