TV-Series
Description
Hanako-kun exists as a ghost eternally bound to Kamome Academy, serving as the Seventh School Mystery charged with preserving equilibrium between supernatural entities and humans. He manifests as a short boy, approximately 150 cm tall, sporting choppy black hair, distinctive amber eyes shaped like crescent moons, and a white "封" seal marked on his left cheek. His attire consists of an old-style male gakuran uniform featuring gold buttons, a white collared shirt underneath, red socks, and a matching black hat. Signature elements include two perpetually floating spirit orbs known as haku-joudai and a kitchen knife wielded as his weapon.

His human identity was Amane Yugi, a middle school student at Kamome Academy in 1969 who suffered from a severe circulatory condition. Defying medical expectations, he experienced a miraculous recovery on his 11th birthday—an event coinciding with the disappearance of his twin brother, Tsukasa. As Amane, he harbored a deep passion for astronomy and nurtured dreams of becoming an astronaut, always carrying a treasured moon rock. He frequently appeared bruised and bandaged but consistently refused to explain the cause. His destiny shattered when he killed Tsukasa using a knife, an act that overwrote his original future as a science teacher. Amane died under unknown circumstances shortly after, transitioning into a ghost.

Functioning as the Seventh Wonder, Hanako-kun commands the haku-joudai for surveillance, teleportation, and combat support. These orbs can also coalesce into a protective cape capable of neutralizing spiritual lightning and enhancing his physical capabilities. His duties encompass monitoring other supernaturals, suppressing harmful rumors, and eliminating dangerous entities. He forged a soul bond with his human assistant, Nene Yashiro, by sharing her mermaid curse; this link ensures she remains human unless submerged in water. Discovering her lifespan is reduced to one year intensifies his commitment to her protection.

Hanako-kun exhibits a dual nature: outwardly projecting a cheerful and mischievous persona, he playfully teases both allies and foes while masking profound guilt and isolation. He habitually conceals negative emotions behind smiles and avoids discussing his past. Though he cares deeply for companions like Nene and Kou Minamoto, he prioritizes their safety above all else, even resorting to manipulation or personal sacrifice. This protective instinct clashes with his reluctance to seek assistance, often resulting in unilateral decisions.

The spin-off "After-School Hanako-kun" depicts his downtime activities, including playing games, falling ill, experiencing accidental gender changes, and unraveling lighthearted mysteries alongside Nene and other supernaturals. These episodes reveal mundane aspects of his existence, such as adopting a Mokke spirit during a Halloween outing and interacting with the exorcist family member Minamoto Tiara, emphasizing his adaptability to human world experiences despite his supernatural state.