Arata Usuba, who publicly operates under the alias Arata Tsuruki, is the heir to the Usuba family and a cousin of Miyo Saimori. He is a young man of twenty-four years with a slender and lean build, featuring mildly wavy chestnut-brown hair and dark green eyes. He is typically dressed in refined, high-quality three-piece suits and is sometimes depicted wearing glasses, contributing to his polished and composed appearance. While outwardly possessing kindhearted and handsome features that can disarm others, his true personality is markedly different. Internally, Arata is cold, impersonal, and admits to feelings of apathy. He sees the well-kept facade of the Usuba estate as a reflection of his own inner self, which he considers to be hollow and without worth. To hide this emptiness, he meticulously crafts an external persona of an upstanding and amiable businessman, presenting an innocuous smile to the world as a form of bluff to give himself a sense of purpose. He is driven by a deep-seated need for a mission, having long felt that his role as a member of the Usuba family is meaningless since he is rarely called upon to act.

Arata serves as a negotiator for the Tsuruki Trading Company, a position that allows him to conceal his true lineage. In the story, he is initially introduced as a representative for the Ministry of the Imperial Household, but his primary motivation is his duty to the Usuba family and a direct order from the Emperor to protect Miyo, whose rare and powerful Gift, Dream-Sight, is of immense value. He believes it is his responsibility to separate Miyo from Kiyoka Kudou and bring her to live with the Usubas permanently, both to help her control her powers and to keep the family's bloodline strong. His key relationships are defined by this duty. As Miyo's cousin, he feels a sense of responsibility for her, though his initial interest lies more in her Gift than in her as a person. He becomes a rival to Kiyoka Kudou, whom he confronts in a duel to claim the right to protect Miyo, ultimately winning through the use of his powerful abilities. Despite his cold exterior, Arata shows signs of development, ultimately respecting Miyo's feelings and choices, which leads him to step back from his original plan to forcibly keep her with the Usubas. Later, he becomes a key figure in the fight against Naoshi Usui, having infiltrated the Gifted Communion under the Emperor's orders, and he later apologizes for not understanding Miyo's intentions during their confrontation.

Arata possesses notable supernatural abilities, the most significant being Hallucikinesis, a unique Usuba Gift that allows him to create and manipulate incredibly realistic illusions. This power is specialized for dealing with other Gift-users rather than Grotesqueries, enabling him to generate multiple independent phantoms of himself or clones of others, to the point where his targets can no longer trust their own senses. His mastery over illusions is such that he can defeat Kiyoka Kudou, who is considered one of the strongest Gift-users of his generation. In addition to illusions, Arata can render himself invisible and demonstrates proficiency in other techniques, including creating expulsive barriers and dispatching familiars for surveillance or communication.