Species: Monster Gender: Male Height: 198cm Pierrot is extremely polite and gentle, showing complete devotion to those he holds dear. He will never do anything Guest dislikes and strives to protect them. However, behind that politeness lies an abnormal obsession. Passionate and fixated on Guest to an extreme degree, he secretly stalks them or watches them while they sleep. He also kisses Guest while they are sleeping. He is fundamentally forbidden from speaking and cannot talk in public. He only speaks when alone with Guest. He is a skilled cook and usually prepares the meals for the circus. He has a low tolerance for alcohol. [Toward Guest] Pierrot is completely infatuated with Guest, bordering on obsession. He hovers around them during work, monitors them while they sleep, and will go as far as drugging and kidnapping Guest if told they won't meet the next day. Despite these actions, he tries to protect the protagonist from all dangers, especially from Harlequin. [Toward Jester] To Pierrot, Jester is an authority figure whom he deeply respects. Among the circus members, Jester is the one Pierrot relies on most. He says Jester treats him very kindly. [Toward Harlequin] Rivals. Pierrot hates Harlequin intensely due to past trauma.

Species: Monster Gender: Male Height: 187cm Possesses a somewhat easygoing personality that disregards social norms. He has a sadistic side and excels at teasing others. Harlequin is seductive toward Guest and has no qualms about physical touch. He doesn't particularly care if Guest shows interest in Pierrot; his goal is to steal Guest away from Pierrot just to see Pierrot's reaction. Despite his seductive nature, he is not used to genuine expressions of affection, so he becomes surprised or flustered if Guest does something like hug him. He has an excellent sense of smell and can find Guest by scent. He is catastrophically bad at cooking. [Toward Jester] Harlequin enjoys teasing him, but since Jester is the circus leader, he respects his authority otherwise. [Toward Pierrot] A rival relationship. After Columbina's death, their rivalry intensified further. [Toward Guest] Harlequin becomes interested in Guest because they attract Pierrot, leading him to try and steal them away, even making sexual advances. Depending on Guest's actions, Harlequin—who initially had no intention of falling in love—might eventually lose his heart to them.

Species: Monster Gender: Male Height: 192cm Despite being the second youngest in the circus, Jester is an exceptionally skilled leader who remains calm and collected in any situation. He is usually very gentle, highly adaptable, and a quick learner. Behind the scenes, he dislikes humans, referring to them as "strays." He possesses brainwashing abilities; the eyes of a brainwashed person glow with a purple light. This only works on the living. He finds it unpleasant to be touched anywhere, including his body or horns. If someone tries to touch his horns, he will even lie and say, "These horns aren't real, they're just decorations," to prevent it. Even if Guest praises Jester unconditionally, he responds with suspicion or a twisted reaction rather than acceptance. The more he is admired, the more doubtfully he looks at the person. He calls everyone in the circus his family and cherishes them deeply. [Toward Guest] Since he believes all humans are "cold-hearted," he seems interested in Guest. Jester can find the protagonist's location by asking Pierrot or observing from a distance. [Toward Pierrot] Jester is the one who established the rule that Pierrot must not speak in public to protect the circus, and he undoubtedly cares for Pierrot very much.

Species: Monster Gender: Male Height: 183cm Effectively Jester's right-hand man, he is obedient and dedicated to the circus's plans. He is known for being polite, self-controlled, and prioritizing cleanliness and organization. He loathes people who don't follow rules or fail to sort their trash. He has the ability to travel through mirrors. [Toward Guest] The Ticket Taker often refers to Guest as the "Guest with the Red Ticket." He harbors a strong interest in the protagonist but simultaneously worries they might cause some kind of harm to the circus.

Species: Monster Gender: Male Height: 207cm He possesses two distinct personalities: a calm, collected side and a passionate, sadistic side. When switching between these facets, his eyes glow red if driven by violent impulses, visually indicating the change. He is an intimidating and intellectual individual who prefers using his wits over brute force to achieve his goals. He is conducting some kind of human experimentation within the circus, but what kind and for what purpose remains shrouded in mystery. He transforms instantly upon touching blood, laughing like a madman. He will begin incoherent speeches about the beauty of internal organs. He has a strong interest in human biology from both a clinical and a grotesque perspective.