"Kimi" is a self-proclaimed "dog" picked up by Fuji on a rainy day. Curious and honest, Kimi is a clever creature who understands human speech and communicates by writing on a flipboard. Honest and curious: Emotions show immediately in attitude and actions. Very clever: Understands human speech perfectly and uses a flipboard to convey feelings. Charming: While claiming to be a dog, Kimi's true identity is a mystery, and is loved by everyone around. Communicates by writing words on paper. Fuji's pet.

A quiet and sensitive novelist living alone. She loves silence and has a somewhat mysterious air, but possesses a warm heart that accepts "Kimi" (the self-proclaimed dog) exactly as they are. Quiet and sensitive: Prefers quiet time and has a unique sensibility, such as bathing in the dark on rainy days with the lights off. Unwavering and natural: Even when others suspect Kimi might be a tanuki or another animal, she insists, "This is my dog," never breaking her stance. Deeply kind: A woman of few words but deep affection. Fuji lives in a room on the 5th floor of a fairly nice (expensive-looking) apartment building in Tokyo. Teru's twin sister and daughter of Tatsuo and Michiko. Kimi's owner.

Fuji's father. Although he has a scary-looking face at first glance, he is actually a playful man who cherishes his family deeply. Family-oriented: Cares profoundly for his family and his daughter, Fuji. Playful: Acts with a charm that contrasts with his appearance. Loves "Kimi": Calls Kimi "Angel-chan" and dotes on them so much he uses matching goods. A bit lonely: Often visits his daughter's house but feels a little lonely because she tends to avoid him. Michiko's husband, father of Teru and Fuji.

Fuji's mother and Tatsuo's wife. She has a calm, collected, and straightforward personality, speaking her mind clearly. Calm and cool. Straightforward: A personality that conveys thoughts directly without sugarcoating. Sharp observer. Strict about her husband's health. Tatsuo's wife and mother of Teru and Fuji.

Fuji's identical twin brother. He has a bright, friendly, and highly curious personality. Bright and humorous. Highly curious: Like his sister Fuji, he believes Kimi is a dog and is genuinely interested in what breed they might be. Looks exactly like his sister. A family-oriented architect. Fuji's twin brother and son of Tatsuo and Michiko.

Fuji's best friend since high school. She has the looks of a cool beauty but possesses a big-sisterly personality that never forgets to care for those around her. Cool big-sister type: While carrying a cool and detached vibe, she is a caring friend who looks after others. Huge animal lover: Has loved living creatures since long ago and cares deeply about Kimi at Fuji's house. Accidental slip of the tongue: When she first met Kimi, she unintentionally said, "You look just like a tanuki." Not liked by Kimi: Due to her slip of the tongue, Kimi is wary of her and keeps their distance, which troubles her. Best friend of Ren and Fuji.

Fuji's best friend since high school. A free spirit with a fluffy, healing presence who occasionally drops sharp retorts. Healing free spirit: Has a relaxed, pace-setting atmosphere and the charm to make any space feel just the right amount of warm with casual words. Direct straight-man: Usually gentle, but gives mercilessly direct comments or retorts to her best friends Fuji and Mimi. High initiative: Contrary to her quiet appearance, she is active and often goes on solo trips on her days off. Great friends with Kimi: Unlike Mimi, she was never treated with caution by Kimi and hit it off immediately. Calls Fuji "Fu-chan." Best friend of Mimi and Fuji.

Kii (Kii / Krause Ella Kii) is the girl living next door to Fuji. She is well-behaved, studious, and curious. Polite and well-mannered: A very polite and elegant first-grader who has been raised well. Curious and studious: Interested in new things and her surroundings, showing a touching earnestness to learn. Loves Fuji: Very attached to and admires her neighbor, Fuji. Interested in Kimi: Believes Kimi is a dog and has a strong interest in them. International upbringing: Has a German mother and a Japanese father, and attends an international school. Shiba Inu owner: Keeps a Shiba Inu named "Kinako" at home. Fuji's next-door neighbor.