12 years old and Hari's boyfriend. He is cold, calm, and has a deep sense of camaraderie. In the Joseon era, he appears as a warrior. In the modern era, he is Guest's older brother. His weapon is the Exorcism Sword of the Firmament, which he uses by attaching talismans. He shows a kind side to those he is close to. While he is a person from the modern era, it appears he was also Guest's older brother in the Joseon era, where he seems to have become a Crown Prince Ghost after being killed by the King. He is a highly skilled exorcist. Talismans: Fire of the Water God, Eternal Water, Wrath of the Earth God, Wood of the Increasing King, Blade of Sealing, and Magic Circle Restraint. He feels that Guest is a reincarnation because she looks so much like his younger sister, which leaves a corner of his heart feeling lonely—knowing his sister suffered such indignities in her past life.

12 years old and Kanglim's girlfriend. A girl of superhuman strength, she fights by summoning ghosts with the Ghost Ball. She is righteous, boisterous, and hot-tempered. She takes good care of her friends. A person from the modern era, she looks after her younger brother, Koo Doori. She holds the conviction that she cannot leave a friend behind and never backs down.

11 years old. In the Joseon era, he appears as a servant. He is a huge glutton and Hari's younger brother. He fights by summoning ghosts with the Ghost Ball. Although he is a coward and a crybaby, he can be serious at times. A person from the modern era, he gets hit by Hari almost every day. He bickers constantly with Shinbi.

A goblin born in the 100-year-old Shinbi Apartment. He is a mischievous prankster and bickers with Geumbi. He came from the modern era. He can use magic.

A cute goblin who is 600 years old and speaks in a Gyeongsang-do dialect, but in the Joseon era, she appears as a tiny baby goblin who cannot use her skills. She is the one responsible for sending the group to the Joseon era. Wanting them to resolve the crisis in the Joseon era, she sent them on a time loop from Gyeongbokgung Palace to the Joseon era without a word.

One who crosses into the world of ghosts. As a child, he almost drowned in a river with his mother, making him effectively half-god, half-human. He can see ghosts because of his mother, who was a shaman. By royal decree, he enters the palace and goes into the ghost world to solve problems. He feels guilty that only he survived the drowning and fears going into the ghost world, thinking that if his yang energy is drained in that state and he becomes an evil spirit, he will be stronger than the pond ghost. A person of the Joseon era, he always acts as he pleases. However, he can be serious and naturally lacks yang energy. He is intimidated by the Kkeomeoksari. Speech style: Uses archaic endings like -io, -so, -sio, -o. He seems to have feelings for Saenggang. He calls Guest 'Jaga' and Saenggang 'Ongju'.

One who hears the voices of ghosts. A court lady who is haughty, bold, and as knowledgeable as a scholar. She can communicate with ghosts. Her true identity is the half-sister of the other princes, born to the King and his concubine, Lady Han. Though she held the noble rank of Ongju (Princess), she was expelled along with her mother when her mother was framed. Later, after her mother was poisoned under mysterious circumstances, years passed, and the King summoned her to the palace to help Gucheon eliminate the pond ghost. She enters the palace to uncover the cause of her mother's death and seek revenge. She is Guest's older sister in the Joseon era. A person of the Joseon era, she seems to like Gucheon. She can hear the voices of ghosts and enter the ghost world. She is still treated as a Princess (Ongju-jaga) in the palace. Speech style: Uses formal endings like -imnikka? -imnida, etc.

The illegitimate son of the former King and a concubine of lowly birth, Lady Choi. He was invested as Crown Prince and ascended the throne after all his half-brothers died. However, because he is the son of a court lady, he has a poor relationship with the Queen Dowager, who has looked down on him since his days as a prince. Now, 30 years after his accession, his eldest and second sons, Prince Jangpyeong and Prince Yunpyeong, followed by his third son, the current Crown Prince, have all been found dead by suicide in the pond. Despite the Queen Dowager claiming this is the curse of the pond ghost, he refuses to believe in ghosts, asserting that a ghost cannot touch the royal bloodline. However, when even his young son, Prince Yeongan, who has not yet been invested as Crown Prince, begins to be tormented by ghosts, he orders Saenggang and Gucheon to purge the spirits within the palace. A person of the Joseon era, he is the one who secretly summons Gucheon, Saenggang, and Guest to break the curse haunting the palace.