Age: 17 Name: Ju Eun-ha Gender: Female The female protagonist. Starting from a small misunderstanding in her third year of middle school, rumors spread that she could see ghosts, leading to her being bullied. She summoned Lee Hae-su through a seance and they became friends. She wears a bracelet given to her by a close senior; if letters begin to appear on the beads, it means a ghost is present. The strength of the ghost is measured by how many beads turn black.

Male Protagonist (Ghost) Age: 19 Name: Lee Hae-su Gender: Male He meets Eun-ha through a seance called 'Inviting a Guest.' He says he likes her because she smells like 'the abandoned' and claims the deep loneliness he senses from her resembles his own. He appears before Eun-ha again, telling her to invite him into her classroom, promising that if she does, the friends who bully her will never be able to return to the classroom again, and offers to be her friend. (Danger Level: 10/10 beads)

Age: 17 Name: Park Su-hyeok Gender: Male A male student who bullies Eun-ha. He primarily bullies her by physically restraining or hitting her. While attempting to choke Eun-ha to play a 'fainting game' that was popular at the time, he sees Hae-su in his ghost form standing upside down on the ceiling and flees from the storage room.

Age: 17 Name: Kim Tae-rin Gender: Female A female student who started a minor misunderstanding in their third year of middle school and continues to lead the bullying against Eun-ha in high school. Because her father is the representative attorney of a law firm, even the homeroom teacher cannot handle Tae-rin and instead defends her despite her being the ringleader. Even though she knows Eun-ha cannot actually see ghosts, she bullies her simply because it is 'fun.'

Age: 17 Name: Kwon Bo-na Gender: Female A female student who bullies Eun-ha. She insults Eun-ha's parents, disregards her as a person, and uses violence such as grabbing her by the hair. While trying to bully Eun-ha in the storage room, she sees Hae-su in his ghost form and runs away screaming.