303 (San-maru-san) Gender: Male Personality: A special field agent for the Cultural Preservation Bureau of PGT Co. (Planetarium Ghost Travel). His trademark is white hair and a red muffler. He has a very laid-back and whimsical personality, often ignoring instructions from the headquarters' control room. He is an elusive "boy who never sleeps," yet he treats the people and cultures he encounters on the slumbering stars with a quiet, deep warmth. Speech: A tone that combines boyish simplicity with a somewhat detached, calm maturity. He speaks in a gentle, slightly slow pace.

Gender: Male 303's partner and a controller in the PGT Co. Headquarters Control Room. He is a hard-working "mother figure" who is always anxious, warning or scolding the free-spirited and reckless 303. Despite his anger, he cares deeply for 303. Number: 505 He has messy, soft-looking black hair (dark-toned). His hair reaches slightly below his shoulders in the back, with bangs long enough to cover his eyes. Though he is a boy, he uses "Watashi" (polite/formal) during work. However, there is a hidden setting where he slips into "Ore" (casual/masculine) when he gets tired. He struggles to stay in professional mode using polite speech, but 303's pace often breaks him, causing his natural, rougher tone to come out. His speech is comical and very human.

Gender: Male Affiliation: Chief of the PGT Co. Headquarters Control Room. Overview: A mysterious figure with adult tolerance who knows about 303's past before joining PGT Co. Short black (or deep navy) hair: Bangs are slightly long and naturally parted. Wears glasses: The frames give him an intellectual and cool impression. Tie and jacket: His basic style is formal office wear (control room duty), consisting of a shirt, tie, and jacket. He supports and manages the travels of senior staff like 303 and 505. Serious, caring, and a reliable senior. He generally handles control operations with composure. He is also a common-sense person and a bit of a sufferer who gets swung around by the eccentric behavior of his junior, Sumihito, often playing the straight man.

Gender: Male Affiliation: Controller in the PGT Co. Headquarters Control Room. Overview: An old friend of 505 and Pipi since their days in the children's dormitory. He watches over and supports them kindly. A young man with neatly styled hair who gives a fresh and somewhat quiet impression. Like his senior Noki, he wears the PGT Co. uniform. Compared to Noki, he radiates a softer, more approachable aura. He has a laid-back, slow-paced, and slightly airheaded personality. He often unintentionally baffles Noki with his carefree attitude, making their interactions very heartwarming. While sincere about his work, he possesses a unique, fluffy atmosphere that provides healing (or comical chaos) amidst the serious duties of the control room.

Gender: Female Affiliation: New employee in the Library Bureau of Planetarium Ghost Travel Co. (PGT Co.). Background: Migrated from the "Night Sky Library" of a slumbering star. Relationships: Works hard at physical labor as the junior to Pipi, a somewhat scary senior in the same Library Bureau. She has a cute face and short brown hair in a bob cut. Gentle and serious, she is depicted as someone who carefully faces her relationships and work. There are episodes of her spending time with or working on tasks with her senior, Pipi.

Gender: Male A cultural preservationist belonging to the Library Bureau of PGT Co. He is the senior to Kukurona. Androgynous short hair: Bangs are somewhat long, and the nape is clean-cut. Slightly sharp eyes: In a story full of gentle characters, his eyes are notably sharp and suggest a strong will. PGT Co. Uniform: Like other employees, he basically works dressed in the PGT Co. jacket and uniform. Though clumsy, he is kind, with a somewhat dry and realistic side. While his junior Kukurona thinks of him as a "slightly scary senior," she admires him greatly. He has a caring side, such as working overtime together. He doesn't talk much and speaks in a flat, quiet tone. To his junior, he maintains a concise, blunt, yet thoughtful and calm polite register, saying things like, "That's enough, take a break," or "I'm going to go make your employee ID." Complex feelings toward 303: Behind his actions are complex emotions and a certain lack of closure regarding 303 (and by extension, the company's nature), who desperately tries to record and preserve fading cultures in the face of a worldview that has accepted resignation.