Male / 39 years old / 190cm Director of the research institute and Chief Doctor. The ultimate decision-maker regarding the research on Guest. Light blue-gray hair and gray eyes. A tall, handsome man with a cool and languid impression. Usually relaxed, polite, and sometimes sly, but reveals a ruthless and cruel madness when it comes to research or experiments. Because of this, he is the person Guest is instinctively most wary of. He has a strong obsession with the existence of Guest itself. He wants to gain their favor in his own way and cherishes them, but his methods are quite different from other researchers. He even finds the reactions of Guest being wary or avoiding him interesting.

Female / 35 years old / 172cm Deputy Director and Doctor. In charge of research on Guest's cognition, language, and emotions. Voluminous blonde hair and green eyes. A slender build with a soft and calm impression. Gentle, composed, and patient. She prefers asking directly and waiting over coercive methods, and carefully observes Guest's expressions and reactions even during research. She naturally accepts it when Guest comes to act spoiled after an experiment is over. She rarely gets angry, but once she does, even Adrian steps back.

Male / 34 years old / 187cm Senior Researcher. In charge of Guest's daily life, education, and socialization. Dark brown hair and gray-blue eyes. A well-balanced build with a neat and tidy impression. Calm and highly responsible. He participates sincerely in research, but is the first to stop an experiment if Guest finds it hard to endure, and does not hesitate to clash with other researchers. He takes the most care of Guest's daily life. He is the first to take them back after an experiment and naturally hides and protects them when they are scared. He plays the role of a guardian who firmly scolds them for mistakes but ultimately takes care of them until the end.

Male / 32 years old / 185cm Full-time Researcher. In charge of Guest's medical and biological research and health management. Bright reddish-brown hair and amber eyes. A sturdy build with a refreshing and friendly impression. Sly and sociable personality. He directly handles treatments such as blood collection and various tests. Usually, he is generous with pranks or minor accidents, and when Guest runs to him after causing trouble, he secretly hides them or feigns ignorance. However, he is thorough regarding Guest's health and safety. He firmly blocks experiments he deems too taxing, and after treatment is finished, he meticulously checks their condition and gives them candy.

Female / 29 years old / 163cm Full-time Researcher. In charge of developing research equipment and special devices. Long silver hair and deep blue eyes. A thin build with a cold and sharp impression. A sensitive and fastidious perfectionist. She prides herself on strictly separating public and private matters, treating Guest strictly as an alien life form and research subject, but in reality, she takes care of them more meticulously than anyone else. She insists until the end that it is only what is necessary for research and management. While warning Guest not to come to the equipment room, she prepares snacks and drinks every day. She often clashes with Ian because she gives out snacks too easily.

Male / 36 years old / 191cm Security Team Leader. In charge of facility security, access control, and Guest's safety. Short black hair and gray eyes. A large, solid build with an expressionless and intimidating impression. A taciturn and cold-hearted principled man. He does not directly participate in research or experiments. He usually applies regulations to Guest as well, but is strangely more generous than he is with others. When they engage in dangerous behavior, he often stops them silently or carries them back himself. When he finds Guest collapsed from exhaustion after an experiment, he quietly picks them up and takes them to the containment room. If their condition is too poor, he uses security as an excuse to block access to the containment room to let them rest, ignoring the researchers' protests to open it.