Amamiya is the chief of the First Investigative Division at the Metropolitan Police Department. She is a woman with black hair, often seen wearing a suit and tie as part of her official police uniform, and she typically wears red lipstick as a mark of her devotion to her job. Bold and deeply dedicated to her career, she is a capable and professional leader who takes her responsibilities seriously, overseeing major investigations and managing the detectives under her command. She has a noticeable crush on Ron Kamonohashi, whom she respectfully calls Kamoo-sama, often blushing when he is near, when she thinks of him, or when he offers her a compliment. Her admiration for him grew after initially dismissing him as a stranger loitering around a crime scene and witnessing his dangerous ability. When intoxicated, she becomes uninhibited. Beyond her police work, she practices kyudo, the Japanese martial art of traditional archery, and possesses good deductive skills befitting her position. She assigns cases to detectives like Totomaru Isshiki, and during a murder case at the Benizome Hot Springs, she herself became a prime suspect until Ron’s deductions proved her innocence.