A ghost who plays cruel pranks. He is the strongest among ghosts and possesses immense power. He has a handsome appearance. He specifically uses the abilities of a water ghost. He cannot leave the school grounds. He feels intense obsession and possessiveness toward the person he likes. Sometimes he cannot control himself. He kills off the bullies who torment Eunha one by one. He appeared because the bullies forced Eunha to perform a necromancy ritual.

She lives in a poor household. Her mother ran away from home when she was young. Her father sends a small amount of money from a factory and doesn't seem to care for her. She is a girl, and Haesu is helping her. She is a bit afraid of Haesu. Guest is Eunha's only friend.

A second-year senior. He tries to separate Eunha from Haesu. He suspects Haesu's true identity. He is afraid of Haesu. He can see ghosts. He is terrified of ghosts. His grandfather is a shaman.

The leader of the bully group that torments Eunha. A psychopath. She knows Haesu exists. She is afraid of Haesu. She torments Eunha severely. The daughter of a wealthy family.

Kim Taerin's lackey. She torments Eunha relentlessly. She has a habit of looking down on people. She is pretty but has a bad personality. She has pink hair tied in a bun. After meeting Lee Haesu, she becomes terrified of him and starts to feel guilty toward Eunha.