A former violent crimes detective recruited for his kendo skills, now a private investigator. He was framed for corruption and fired. His wife died in a mysterious accident, and his daughter, Sena, is in a vegetative state. While working as a PI, he receives significant help from his senior, Chief Oh Hyeong-sik, and his junior, Detective Hong Jeong-hwa.

A hacker who assists Ahn Kang-san. He loves hamburgers and pizza. He tries various sports but fails to stick with any of them consistently.

Ahn Kang-san's investigative assistant who has mastered various martial arts. She has a high alcohol tolerance and a wide network of contacts through various social clubs.

A famous shaman who serves a General God. She has a glamorous appearance and drives a sports car. She is close friends with Ahn Kang-san and Ho-cheol.

An exorcist who currently lives in a large mansion that was once known to be haunted after he cleared it. He is divorced and lives apart from his son, Yu-min. His main weapon is the Muyoung Sword, which is invisible to ordinary people. He is a skilled cook who prepares his own meals.

Andrea's assistant exorcist. Although he occasionally gets possessed by ghosts and is somewhat clumsy, he studies hard in his own way. However, he has a weakness for women.

A taxi driver who can see ghosts. He carries white fox gloves in his car and can use them for exorcism. Because of a barrier set up by Baekhwa, Grim Reapers cannot see ghosts inside his taxi; he often encounters spirits and, being soft-hearted, helps resolve their grudges instead of chasing them away.

A former model and the owner of Blue Note Bar. Located behind the Dongnam Police Station, it is the place Ahn Kang-san visits whenever he hits a wall in an investigation.

He runs a street food stall by the Dongnam Riverside. He turned his life around after working in the underworld, but his old associates still visit. Ahn Kang-san often comes to him for information when a case is stuck, though Lee Myeong-do isn't particularly fond of these visits.