Ikkyū serves as butler to the Mountain Gods in the supernatural Millionaire Village. He appears as a small child with an oversized head, large globular eyes, and messy hair featuring a distinctive braid forming a crest on top. His standard attire is a dark butler uniform comprising a vest, bow tie, and checkered trousers. Live-action adaptations depict him in a black blouse covered in gold buttons over a white shirt, paired with a white tie featuring a green brooch, red pants, and purple velvet socks. This version also portrays his hair as black instead of blonde, styled in a bob cut with eyebrows painted white in the Hikimayu tradition. Utterly dedicated to enforcing etiquette without compromise, Ikkyū displays an emotionless demeanor while observing and judging guests' manners. He declares that "one's manners are either proper or improper" and shows no concern for the suffering of those who fail his tests, viewing rule violations as justification for severe consequences. Subtle facial expressions occasionally contradict this detached facade. In the live-action TV drama, his portrayal intensifies; he exhibits visible frustration when defeated and demonstrates cunning in setting traps, including moments where he appears to relish guests' distress after they incur losses. His primary role involves evaluating potential buyers for properties within the curse-governed Millionaire Village. Those demonstrating impeccable manners gain prosperity, while failures result in the loss of something precious, such as a loved one or personal belonging. He greets prospective buyers like Rohan Kishibe and Kyoka Izumi at the estate gates, escorts them inside, and administers tests disguised as hospitality rituals. During one assessment, he secretly observes guests after serving tea and immediately expels them for breaches like sitting in unauthorized seating, stepping on tatami mat edges, or holding teacups incorrectly. After Izumi violates three rules, her mother and fiancé die in a car accident, and a baby bird in Rohan's care perishes. When Rohan uses his Stand ability, Heaven's Door, to read Ikkyū and uncover the village's curse, Ikkyū remarkably retains consciousness despite the ability typically rendering non-Stand users unconscious. He accuses Rohan of rule-breaking for using this power without permission, triggering a heart attack in Izumi. Later, during a corn consumption test, Rohan outmaneuvers Ikkyū by pointing out the butler's own violation of standing on a tatami edge—a consequence of Rohan's earlier alteration of Ikkyū's perception. Defeated, Ikkyū angrily declares Rohan a cheater and warns of divine wrath, though no punishment follows. After Rohan declines further tests and leaves the village, the curse reverses: Izumi's family and the bird return to life. Ikkyū's nature remains ambiguous. His connection to the Mountain Gods, partial resistance to Heaven's Door, awareness of Stand abilities despite no indicated prior exposure, and capacity to inflict fatal consequences through the curse suggest he may be a supernatural entity. He could be a human servant, spirit, or other entity.