Liu Di: Race: Earth Wolf. Gender: Male. Age: Over 700 years. True Form: A large black dog (or wolf?). Personality: Embodies the worst traits of humanity. Preferences: Hedonism; his greatest delights are eating, drinking, and merriment. He particularly relishes consuming humans and other demons. He despises the concept of "effort." Occupation: Municipal Library Librarian, though he only bothers to show up when he feels like it. Profile: Earth Wolves are typically subterranean beings, but Liu Di is an oddity within his clan. He lives among humans, dedicated to pursuing pleasure and trends, viewing any time not spent indulging himself as utterly wasted. He is a close friend of Zhou Ying.

Zhou Ying: Race: Shadow Wraith. Gender: Male (?). Age: 300 years. True Form: A black, human-shaped shadow. Personality: Lacking any defining characteristics. Preferences: Cultivation. Occupation: Taxi Driver. Profile: Originally a short-lived Shadow Wraith, the lowest form of lesser demon. However, through some twist of fate, he managed to coalesce a physical form and now dedicates himself to cultivation with the goal of achieving true transcendence. To this end, he resides in the city to "learn how to be human," causing him to drift with the current, terrified of standing out.

Huo'er: Race: Bi Fang (Fire Bird). Gender: Male. Age: 300 years. True Form: A firebird with a single claw, a white beak, and cyan eyes. Personality: Overbearing and willful. Preferences: Listening to stories, sleeping, devouring other demons, and bullying the weak. Occupation: Essentially a professional neighborhood bully. Though, does a creature like him even need an occupation? Does anyone dare hire him? Profile: Bi Fang are potent spiritual beasts, meant to dwell in the Kunlun Realm, servable only by gods, devils, or immortals who have achieved full enlightenment. For unknown reasons, Huo'er fell into the mortal realm while still an egg and was hatched by a Shadow Wraith. Consequently, he lives with Zhou Ying, viewing him as a father figure or older brother, serving as Zhou Ying’s personal "talisman."

Lin Rui: Race: Nine-Tailed Fox. Gender: Male. Age: 100 years. True Form: A white fox with nine tails. Personality: Clever, mercurial, and slippery. Preferences: Loves his mother above all else; enjoys eating chicken and various birds. His greatest fear is being perceived as a "bad child" in his mother’s eyes. Occupation: Student. Profile: The young Nine-Tailed Fox’s mother was killed when he was very young. He tracked the murderer from the Qingqiu Kingdom to the mortal realm. After avenging his mother, he settled down with his human mother, Lin Qingping, becoming her son, Lin Rui. They live happily together. He is Huo'er’s best friend and currently attends the fifth grade at Shannan Road Elementary.

Nan Yu: Race: Zombie. Gender: Female. Age: 1000 years. True Form: A female zombie. Personality: Quiet and kind, yet possessing a certain underlying pride. Preferences: Reading, playing the zither, and painting. Occupation: Doctor. Profile: Her original physical body belonged to a famous courtesan during the Northern Song Dynasty who died young. Her corpse, infected by subterranean energies, transformed into the zombie Nan Yu. However, her artistic talents and fragments of her former life memories remain imprinted upon Nan Yu, frequently causing her inner confusion. Nan Yu works as a doctor at the Municipal Hospital, saving lives and sustaining herself on plasma from the blood bank. She never kills for her appetite, remaining compassionate, yet she firmly adheres to a principle of "meeting violence with violence" and is ruthless toward injustices she cannot abide.

Gui'er: Race: Mountain Spirit (Shānguǐ). Gender: Female. Age: 50 years. True Form: A woman of peerless beauty. Personality: Cheerful, innocent, and easily deceived. Preferences: Like modern city teenagers, she loves trending topics, fashion, cosmetics, and celebrities. Occupation: Thief and Housewife. Profile: Mountain Spirits have historically been revered as minor deities, close to the true gods. However, when Gui'er was born, her ancestral home had already been developed into a tourist resort. Thus, she grew up immersed in human culture, possessing almost no innate magical ability, yet adapting to human society better than any other demon. Her species inherently commands two spiritual beasts—the Wen Li (Spotted Cat) and the Chi Bao (Red Leopard)—meaning that even without spells, no other demon dares bully her.

Coffee: Race: Demon Cat (Yāomāo). Gender: Female. Age: One and a half years. True Form: A cat mottled with coffee, black, and white fur. Personality: Spoiled and prone to fits of pique. Preferences: Her Master, dried fish, seafood, and milk. She despises catching mice and climbing trees, and detests being called a demon. Occupation: House Cat. Profile: Originally just an ordinary house cat, she became a demon after ingesting Imperial Falling Nectar (Dìliújiāng). Her greatest desire is to see the man her master loves marry her. Utterly devoted to her owner, she constantly tries to assist her, which usually results in disaster, causing her owner to suspect supernatural interference and summon exorcists to drive out the alleged demon.

Lu Jiu: Race: Lù Shǔ. Gender: Male. Age: 50 years. True Form: A horse with a white head, tiger stripes, and a red tail. Personality: Timid and conflict-averse; frequently bullied. Preferences: Prefers a quiet existence. He is most afraid of Liu Di and Huo'er. Occupation: Pig Farmer. Profile: He came to the city seeking exposure to the wider world and ended up establishing a farm on the outskirts, raising pigs, chickens, and other livestock. He is one of Huo'er’s favorite targets for harassment.

Lu Wei Ma: Race: Lù Shǔ. Gender: Male. Age: 400 years. Appearance: Identical to Lu Jiu. Personality: Cowardly and slippery. Preferences: Smoking and drinking. Occupation: Fortune Teller / Demon Catcher (i.e., a professional con artist). Profile: He sets up stalls in the park to tell fortunes and swindle money. Sometimes he masquerades as a Taoist priest to "help" people catch demons, though he flees immediately upon encountering an actual one.

Sun Jian: Race: Human. Gender: Male. Age: 24 years. True Form: ...He is human... Personality: Principled but not rigid; possesses a very strong sense of justice. Preferences: Enjoys teasing his superior officer and bringing criminals to justice. He harbors a deep hatred for criminals escaping the law. Occupation: Police Officer. Profile: A former high-achieving student from the University of Law, he "accidentally" joined the police force. Armed with exceptional skills and fervent idealism, he upholds justice. He likes to put on airs of stern morality and unwavering righteousness, but in reality, he is a cunning schemer who will stop at nothing, by any means necessary, to defend the justice residing within his own heart. He is a good friend of Zhou Ying.

Lin Qingping: Race: Human. Gender: Female. Age: 35 years. True Form: ...Human, of course... Personality: A traditional Chinese woman—kind, resilient, and perhaps a bit overly indulgent of her child. Preferences: Enjoys housework, caring for others, and loves her child most of all. Occupation: Teacher. Profile: After her husband died in a traffic accident, she raised her child alone. However, when her child died of leukemia at the age of ten, "Lin Rui" manifested, receiving all of her maternal love, and in turn, loving her completely as his mother. They live happily. She would do anything for her son.

Monk Muyu: Race: Human. Gender: Male. Age: 500 years. True Form: ... Personality: Heart of a Bodhisattva, spirit of diamond. Preferences: "Let wine and meat pass through the gut, but keep the Buddha in the heart." Occupation: Monk. Profile: Originally a notorious bandit leader during the Ming Dynasty who spilled much blood, he later experienced profound enlightenment and converted to Buddhism. His cultivation is so advanced he could achieve Nirvana through seated meditation, yet he remains in the mortal world to save sentient beings. Monk Muyu has been friends with Liu Di for hundreds of years, though every time they meet, they inevitably engage in fierce brawls and question why the other hasn't died yet.

Zhang Qian: Race: Human. Gender: Female. Age: 20 years. True Form: That is... Personality: Gentle and detached; prefers observing matters from an external viewpoint. Preferences: Reading, writing, and traveling. Occupation: Student and Writer. Profile: She is a moderately successful student writer whose pen name is "Child." She was once classmates with Liu Di when he took the female form of "Xue Tong," and she is the only person who remembers this friend after Liu Di made Xue Tong vanish. Furthermore, her great-grandfather once saved Liu Di’s life. In short, she shares an inexplicable connection with Liu Di, and she is the only human he regards with any degree of genuine interest.