Shiro (Land of Ancestors)

was a dog from the Land of Ancestors and a pet of Asura and Indra Ōtsutsuki.

Background
Shiro was the beloved dog of Indra and Asura Ōtsutsuki and often accompanied them when they were playing around their home village. One day, Asura, Taizō and two other friends of them decided to trace down a boar that was roaming around. Shiro was the first to notice it, but the wild animal's statue and behaviour were much more intimidating as expected, so the group decided to flee. When Asura was in real danger of being killed, Shiro bravely jumped in between and tried to attack the boar, but was easily overwhelmed and killed by it. Just moments later, Indra arrived and killed the boar, awakening his Sharingan in the process. Shiro was buried by Asura afterwards.

Personality
Shiro was a happy and adventurous dog, often getting excited by Asura and Indra's games. It was also very protective and loyal, jumping between Asura and a wild boar without hesitation, despite the wild animal's size and strength exceeding Shiro's by far.

Appearance
Shiro was a small dog with a light brown upper body and tail while its lower side, the area around its mouth and the inside of its ears were white. It also had two small, circular white spots above its eyes.

Legacy
It was either Shiro's death itself or the stress coming from the overall situation that awakened Indra's Sharingan. Asura would often visit Shiro's grave to pray. On one anniversary of Shiro's death, Asura's father Hagoromo Ōtsutsuki visited his praying son and, after seeing his love and loyalty towards those he loved, first began to consider naming him the successor of ninshū instead of Indra.

Trivia

 * When written as "白", "Shiro" means "white", while "城" means "castle" and "代" means "substitution".