Motoi

guides Naruto Uzumaki and Yamato through the island, where Killer Bee trained to control the Eight-Tailed Giant Ox.

Background
When Motoi was five-years-old, he and Killer Bee were good friends. After Motoi's father was killed extracting the Eight-Tailed Giant Ox from its previous jinchūriki, Motoi came to hate the Eight-Tails. Bee was soon chosen to be the beast's next jinchūriki and Motoi, just as many other Kumo villagers did, focused his anger towards Bee. He once tried to assassinate Bee to avenge his father, but was disarmed by Bee easily. Despite having his face covered, Motoi assumed that Bee knew it was him, as Bee ungrudgingly greeted him as they used to. After this, Motoi could never bring himself to face Bee, and hadn't spoken to him for thirty years, but in time he came to admire Bee as a village hero.

Fourth Shinobi World War arc
Motoi greets Naruto and his Konoha escorts when they are brought to the island and takes them to their lodgings. After arriving, Naruto tries to get Bee to train him in controlling his tailed beast. Bee refuses, so Naruto comes to Motoi for help with convincing Bee, claiming that he is too stubborn. Motoi grows angry with Naruto for insulting him and insists that Bee must have a good reason. He takes Naruto to the Falls of Truth and instructs him in how to use it, explaining that it will reveal why Bee has misgivings.

Naruto meets an evil version of himself that he cannot defeat. He requests Motoi ask Bee how he defeated his inner demons, but Motoi says that he is in no position to ask anything of Bee, having once tried to kill him. He tells Naruto about Bee's past and Naruto leaves to think. Motoi is later attacked by the giant squid that lives near the island, but Bee saves him. He apologizes for trying to kill Bee when they were kids, but Bee reveals that he holds no grudge and forgives him, lifting his fist. Motoi sheds a tear as he realizes Bee is still his friend, and they bump fists. After Naruto beat his dark half and went onto the next part of his training, Motoi stated that he needed to report back to his village and could not join the others while Naruto fights the fox.