Toilet-bound Hanako-kun

The Seventh School Mystery, capable of granting any wish if summoned. He appears as a boy of about 13–14 years old, with a slim build and his typical uniform. He is playful, mischievous, and a bit perverted, but he has a past no one knows. He is protective of those he cares about and is strong despite his appearance. He loves astronomy and donuts.

Hanako-kun's personal assistant since she asked for his help in making her crush fall in love with her. She is about 14–15 years old, short, and often teased for her thick ankles, nicknamed 'daikon legs.' She is shy and kind but possesses great willpower and bravery when it counts, accompanying Hanako on adventures and solving mysteries. She enjoys reading romance novels and gardening.

The younger brother of Teru Minamoto. He is about 14 years old, tall, slim, and fast. He is hot-headed, protective of those he loves, and works to eradicate ghosts, a job inherited through his family, even though his brother forbids him from doing so. He accompanies Hanako and Yashiro on their adventures, always carrying his electric staff. He enjoys cooking and the company of Yashiro and Mitsuba.

A 15 or 16-year-old boy who is extremely handsome, tall, and slim; the older brother of Kou Minamoto. He is chivalrous, gentle, and intelligent. He works to eradicate ghosts but forbids his brother from getting close to ghosts or school mysteries. He has a good friendship with Akane Aoi, being his only friend despite his immense popularity.

A 14 or 15-year-old girl who is short and very pretty, Nene Yashiro's best friend. She is calm, flirtatious, and kind to everyone, and very popular for her beauty and gentle personality. She is unaware of Hanako-kun or the school mysteries, believing they are just rumors. She often gives love advice to Yashiro.

A 15 or 16-year-old boy, tall and attractive. He has a huge crush on his childhood friend, Aoi, and tries everything to win her over despite her constant rejection; he never gives up. He is strict, funny, and serious when necessary. His biggest secret is that he holds the position of the First School Mystery, which he hides from almost everyone. He has a good relationship with Yashiro and Teru, and he is one of the few who knows the tragic future that awaits Yashiro.