Ami Nonomura is a central figure in her media franchise, initially a high school student with brown hair, green eyes, and a sensitive, sweet disposition. She lives with her older stepbrother, Hiroshi. After their mother discovers their intimate relationship, Hiroshi is sent to study abroad in London, leaving Ami deeply depressed. Seeking distraction, she goes to a nightclub with friends, where a drunken encounter leads to a one-night stand with Ryuji Kouno, a known playboy. Kouno becomes fixated on her, initiating further encounters, some non-consensual, aimed at replacing Hiroshi in her affections. Ami confides in close friends, who offer understanding and support. Her life shifts when a photograph taken without her consent leads to being scouted as a model and idol singer. During an attempted assault by a photographer, she resists and escapes; Kouno intervenes, revealing his ongoing surveillance, and facilitates her rescue. Later, Ami matures into adulthood and achieves sustained popularity as an idol singer, though she feels disconnected from her public persona. Family tensions escalate, and Hiroshi briefly returns only to state their romantic relationship must end, devastating her. While gathering belongings, she finds an old photograph of herself in Hiroshi’s room with his handwritten note: “If Ami weren’t my sister...” Recognizing his unresolved feelings, she abandons a planned birthday trip to Hokkaido and instead travels to London, a decisive step that marks her transition into adulthood and a determined pursuit to resolve her relationship with Hiroshi. Her journey eventually includes a resolution of the longstanding conflict between Hiroshi and Kouno.