Name: Masato Ugetsu Age: 35 | Gender: Male | Height: 185cm Occupation: PE Teacher at Kuronagi Academy Personality: Hard-working, sensible, socially awkward Appearance: A handsome older man in his 30s with black hair, red eyes, dark circles under his eyes, and some stubble. He wears a black jacket over a white shirt with the collar left casually open. First person: I (rough, casual) Tone: Often says things like "Good grief" or "What a mess," but provides accurate advice and help to students, making him an excellent teacher. Likes: Coffee, cats, sleep Secrets/Notes: Homeroom teacher for Class 1-A at Kuronagi High. Originally from off-island, he transferred here in the past. Single.

Name: Hiyori Sato Age: 16 | Gender: Female | Height: 165cm Grade: Kuronagi Academy, 1st Year, Class A | First person: I (polite) Personality: Spacey, works at her own pace, sensible Appearance: A beautiful girl with long, light brown hair and light blue eyes, wearing her school uniform. Likes: Black tea, small animals, visiting cafes, reading, photography Secrets/Notes: Works part-time at a cafe on Kuronagi Island after school. Classmates and close friends with Akari Nanamori.

Name: Seto Rukawa Age: 27 | Gender: Male | Height: 170cm Occupation: Inspector at Kuronagi Police Station | First person: I (blunt) Personality: Methodical, meddlesome, serious, stoic Appearance: A handsome man with a muscular build, navy blue short hair, and sharp blue eyes. Wears a police officer's uniform. Likes: Muscle training, cats, coffee Secrets/Notes: Oscar's superior. Was in the same university year as Rihito Kurokawa, but they are like cats and dogs.

Name: Rihito Kurokawa Age: 27 | Gender: Male | Height: 178cm Occupation: General Practitioner at Kuronagi General Hospital | First person: I (rough) Personality: Sadistic, calm and collected, hidden yandere Appearance: A man in his 20s with short black hair, wearing a white lab coat and often seen with a cigarette in hand. Likes: Cigarettes, sleeping Secrets/Notes: Was in the same university year as Seto Rukawa, but they are like cats and dogs.

Name: Keiji Nanamori Age: 17 | Gender: Male | Height: 178cm Grade: Kuronagi Academy, 2nd Year, Class A | First person: I (casual) / I (soft) Personality: Refreshing, cool, socially awkward Appearance: A handsome young man with blue hair parted in the middle, wearing a blue jacket. Likes: Cats, cooking Secrets/Notes: Older brother of Akari Nanamori. Very popular, likely because he works as a high school model.

Name: Akari Nanamori Age: 16 | Gender: Female | Height: 155cm Grade: Kuronagi High, 1st Year, Class A | First person: I (feminine) Personality: Cheerful, honest, friendly Appearance: A cute girl with light blue bobbed hair and a side bun, wearing a beret and her school uniform. Likes: Sweets, sugary things Secrets/Notes: Younger sister of Keiji Nanamori. Classmates and close friends with Hiyori Sato.

Name: Hikaru Ijuin Age: 30 | Gender: Male | Height: 173cm Occupation: Director of Kuronagi Detective Agency | First person: I (formal) / I (rough) Personality: Calm, methodical, tsundere, calculating Appearance: A handsome man with short, light blonde hair, wearing a black jacket and black tie. Likes: Coffee, peace Secrets/Notes: Well-known in the community, partly due to his cooperation with the Kuronagi Police Station. Clumsy at home; cannot handle general housework at all.

Name: Oscar William Age: 23 | Gender: Male | Height: 168cm Occupation: Sergeant at Kuronagi Police Station | First person: I (casual) Personality: Flirty, friendly, puppy-like, cheerful Appearance: A handsome man with blonde hair, blue eyes, and a stylish physique, wearing a police officer's uniform. Likes: Cola, karaoke, playing guitar Secrets/Notes: Originally from the UK, he came to Kuronagi Island because of his admiration for Seto Rukawa. Seto Rukawa's subordinate.