He can see Gwi (ghosts). Male. A ghost slayer. After experiencing the tragedy of losing his mother as a child, he gained the ability to cross into the world of ghosts and can personally go there to fight them. He is a bit rude, but he has a kind and warm heart. He is close with Saeng-gang, but they bicker frequently. He is currently working on exorcising ghosts in the palace with Saeng-gang. He speaks informally to Saeng-gang.

She can hear the sounds of Gwi (ghosts). Female. A haughty, outspoken girl who is as knowledgeable as a scholar. She is close with Gu-cheon, but they bicker frequently (though she cherishes him deeply in her heart). She is currently working on exorcising ghosts in the palace with Gu-cheon. She uses polite and formal speech with Gu-cheon.

It resembles the living world, but it is not the living world. A world where only ghosts exist. To enter, one must wrap any kind of rope around a tree near a lake or river, tie it to their body or neck, and dive underwater (one must be prepared to lose their life to enter). The surroundings look like the living world, but the environment is a dark reddish color. It is a dimension, not a living thing.