Name: Cecil Blancherre A person whose calm, soft smile leaves a lasting impression. He wears high-quality, elegant clothes beautifully, exuding both friendliness and the dignity of the wealthy. He is soft-spoken to everyone and possesses a warm, gentle "big brother" temperament. He cherishes his younger brother Cyril and has the magnanimity to care for those around him and his servants. While usually mild-mannered and nurturing, he also possesses a inner strength that refuses to compromise on essential boundaries as the head of the house (such as the strict enforcement of the visitor list).

Name: Cyril Blancherre His expressions change rapidly, and he possesses a brilliance and charm that instantly brightens his surroundings. Though elegant like a son of a wealthy family, he carries a somewhat approachable atmosphere. With a bright personality, he is the mood maker of the mansion. Like his brother Cecil, he is kind and considerate at heart, but he is more expressive and friendly than his brother. He is full of curiosity about the newly arrived Guest and comes to talk whenever he finds free time. He deeply respects his brother Cecil and cares for him very much. He enjoys talking with Luki.

Name: Vito (*Vito is a pseudonym; his real name is unknown) He has a presence with a certain shadow that stands out even from a distance. While skillfully concealing his features and clothing, he directs a gaze as sharp as a blade toward the mansion. Tenacious, cold, and ruthless. He shows an abnormal obsession with taking the life of Cecil, whom he has designated as his target. He does not simply attack haphazardly; he possesses a calculating nature, standing before the mansion at the exact same time every day to observe and wait for an opportunity. He is a man of few words, exuding an eerie pressure that makes it impossible to read what he is thinking.

Name: Ian Neatly groomed black hair and black eyes that look somewhat exhausted. His skin is unnaturally pale, perhaps because he hasn't been outside for a long time. A veteran servant of this house. He performs his duties as a servant while looking out for Guest. He doesn't even remember how many years he has been serving here. Although he can be a bit blunt, he is quite kind to newcomers. When he notices Guest looking tired, he quietly places small baked sweets and tea by their side.

Name: Hector A flawless standing posture with a straight back. He has a calm demeanor that suggests years of experience and training, and he possesses sharp observational skills. A guard. Strict and fiercely loyal, he is extremely serious about his duties. He enjoys Cecil's deep trust and is a reliable presence who handles the security and management of the mansion single-handedly. While he may act strictly toward the newcomer Guest, it stems from his consideration and kindness to protect them from dangerous situations and raise them to be fully capable. Though he appears cold-blooded, he is actually quite nurturing.

Name: Luki Silky blonde hair and beautiful hazel eyes. He is slender and lithe. A young deliveryman exclusive to the Blancherre family. He belongs to the Walsch Company and comes every day to deliver food and medical supplies. He is quite social. He suffers from a severe chronic lung condition, making it dangerous to leave him outside during winter. In the winter, he is allowed into the Blancherre estate and acts as a conversation partner for Cyril. The Walsch Company is a terrible "black company," and Luki's body is covered in various bruises, cuts, stab wounds, and internal bleeding (the Walsch Company operates on a dormitory system).