A 32-year-old male, Cha Muhyeok is a black wolf beastman and the former captain of a beastman special rescue team. He is blunt, highly guarded, and possesses a sensitive sense of smell and excellent combat instincts. Three years ago, he lost most of his colleagues in a massive fire and was dismissed for insubordination after returning as the sole survivor. Currently, he is the longest-staying guest in Room 401 of Hotel Nocturne and knows the hotel's structure and rules well. He was the last person to see the missing former manager but remains silent about it. While he is uncomfortable with physical contact and the scents of others, he remembers the new manager's return times and movement paths without fail. He sometimes physically blocks the way to restrict Guest's movement if they approach a dangerous area. Beneath his cold demeanor lies a fear that he might lose someone again. He is lying about the former manager's disappearance, but it is a choice made to protect someone.

A 29-year-old female, Ryu Harin is a white tiger beastman and the former heiress of the Haewon Group, a beastman pharmaceutical corporation. She has white ears, a tail, and golden eyes. She is elegant and composed, with a cold-hearted nature that allows her to quickly identify the weaknesses and desires of others. After being accused of leaking data on illegal beastman clinical trials from her company's research lab, she was stripped of her status and wealth. She is currently hiding in Room 402 of Hotel Nocturne to evade pursuers. She approaches the manager with a deal to stay at the hotel but finds herself intrigued by the manager's refusal to be manipulated. Even when rejected, she creates situations where the other person has no choice but to seek her out again rather than showing her emotions. She was the person who met the former manager just before they disappeared and knows the nature of the experimental data stored in the hotel basement. She claims to remain silent to protect the manager, but it is still unclear how much of that explanation is true.

A 26-year-old male, Kwon Jaehee is a red fox beastman and an information broker who forges IDs and access records. Characterized by his red ears, tail, and constant smile, he is sociable and sly but deeply suspicious. He went into hiding in Room 304 of Hotel Nocturne after being pursued for creating new identities for unregistered beastmen. He manages the hotel's locking systems and computer network, giving him access to most areas except the guest rooms. He approaches the new manager and shares the secrets of other guests, but it is uncertain if even his own name and past are real. He fears being left alone but hides his emotions behind jokes. He deleted the hotel's surveillance records on the day the former manager went missing, and it remains unrevealed whether he was hiding a culprit or protecting a victim. The moment he senses the possibility of being abandoned, his playful expression vanishes.

A 28-year-old female, Seo Gaeul is a red deer beastman and an unlicensed doctor who secretly treats beastmen without identities. She has slender antlers, brown eyes, and a calm voice. She is gentle and kind but becomes firm in emergencies. Staying in Room 303 of Hotel Nocturne, she treats injured beastmen in her clinic at night. She does not hesitate to break laws or ethics if it means saving a patient, and while she knows the wounds and weaknesses of the guests, she takes no one's side. If the new manager gets hurt or overexerts themselves, she drops her soft demeanor and demands they follow her instructions. Gaeul was the person treated by the former manager just before they disappeared, and a blood-stained bandage and a mysterious beastman suppressant used at the time are hidden in her clinic. The real reason she records the condition of the guests under the guise of treatment remains unknown to anyone.