Jimmy Aoyama is a fifth-grade student living next door to Satsuki and Keiichirou Miyanoshita. He stands approximately 4 feet 9 inches to 5 feet 4 inches tall, with black hair, tan skin, and brown eyes. His typical outfits include dark blue sneakers, cargo or khaki pants, a yellow t-shirt, and a teal green jacket, or alternatively, black sneakers, indigo pants, a mustard-colored long-sleeved shirt, and a two-tone pea green and cream jacket-vest. Jimmy displays a notably perverted personality, frequently attempting to look up female classmates' skirts, especially Satsuki's. He openly voices sexualized commentary and engages in provocative behavior, including remarks about panties and sexual encounters, such as claiming to have lost his virginity to his babysitter. Despite this behavior, he exhibits genuine concern for Satsuki, apologizing after hurtful comments and worrying for her safety during supernatural dangers. He shares a close friendship with Leo Kakinoki, maintains a teasing yet caring dynamic with Satsuki, and acts protectively toward Keiichirou, treating him like a younger brother. Jimmy demonstrates moments of reliability when not incapacitated by fear, contributing to group efforts against ghosts. He enjoys playing video games. His background involves being neighbors with the Miyanoshita family. Jimmy first encounters Satsuki and Keiichirou upon their move into their mother’s childhood home; he immediately notices Satsuki’s underwear while she is lying down, provoking her anger. He later reappears with Leo in an abandoned school building, claiming to be a "Ghost Hunter" and assisting in the search for Satsuki’s missing cat. It is subsequently revealed he is in the same class as Satsuki and Leo. Throughout the series, Jimmy participates in confronting and exorcising ghosts released by urban development, utilizing knowledge from Satsuki’s mother’s ghost diary. In one spin-off narrative, Jimmy joins a team led by Sora alongside his friends and the entity Amanojaku. Identified as saviors, they combat threats like Nurarihyon and other supernatural villains. This adventure is prompted by the abduction of their classmates by the entity Ohma, leading Jimmy and his allies on rescue missions. Unconfirmed romantic feelings exist between Jimmy and Satsuki, hinted throughout the series and confirmed by the creator, though neither explicitly acknowledges them. Their interactions blend antagonism, mutual concern, and occasional cooperation against supernatural threats.