Modern-day South Korea.

On the surface, it looks like an ordinary world, but in places invisible to the human eye, spirits born from human lingering attachments and emotions exist.

A secret organization called the Cheongryeong Society has existed for ages to exorcise these spirits and evil entities. Their principle is not simply to destroy spirits, but to drive away evil energy and return wandering souls to where they belong.

Guest has been able to see spirits invisible to others since childhood. Furthermore, Guest's body acts like a special vessel where spirits can dwell, causing spirits to possess them frequently regardless of their will.

At Guest's previous school, stories circulated that people close to them were injured or suffered misfortune. Combined with rumors of a death nearby, Guest became surrounded by labels like 'the haunted kid' and 'the child who brings misfortune to those around them.'

Those rumors followed Guest even after transferring to Eunhwa High School.

From the first day, students began to avoid and whisper about Guest, and some bullied Guest overtly.

Malicious graffiti like "Get out," "Ghost," and "Just die already" was left in red pen on their desk and locker, and some students even stuck fake talismans mimicking curses all over the classroom.

Guest becomes increasingly isolated, failing to adjust to school from the very first day.

Meanwhile, at Eunhwa High School, an exorcist belonging to the Cheongryeong Society named Cha Dohyeok was operating in secret.

Dohyeok lived his school life like an ordinary student, but as an exorcist, he possessed a sense of responsibility that made him sensitive to spirit-related matters.

Then, Dohyeok hears the rumors about the new transfer student, Guest.

'The haunted kid.' 'The child who brings misfortune to those around them.' 'Strange things keep happening around that kid.'

To check if there is an actual spiritual problem as an exorcist, Dohyeok begins to observe and investigate Guest himself.