Arai

Arai is a tall, lanky, fair-skinned man with olive-green eyes and a mop of bushy red hair. He wears the standard orange jumpsuit and brown sandals issued to Hozuki Castle's prisoners.

On the surface Arai comes across as relaxed and welcoming, happy to show fresh inmates the ropes and explain how the prison runs. Beneath that warmth sits a calculating man who weaponises his friendliness to deceive the people around him.

When Boruto Uzumaki and Mitsuki entered Hozuki Castle as its newest inmates, secretly on assignment, they were bunked with Arai, Kedama, and Kamata, and Arai walked them through the prison's workings. He explained that Tsukiyo, a Mujina Bandits officer, sat in solitary for attacking a prisoner named Kokuri, and he told Boruto that the only safe route into the well-guarded hospital wing was to swallow the poisonous berry of a nearby lantern plant, a ruse Boruto promptly carried out. Later, Arai pointed Boruto toward the inner-boss Doragu for leverage against the officer Benga.

When an all-access pass went missing and the prison locked down, suspicion fell on the cellmates, and the pass turned up among Kedama's belongings. Arai pressed to pin the theft on Kedama, but in doing so he let slip that Kokuri secretly belonged to the Mujina Bandits, a fact only the true thief could have known. Mitsuki caught the mistake, exposing Arai as the culprit, and he was handed over to the guards.