Hiroshi Nonomura is a supporting character in the Cream Lemon series, primarily appearing in the story arcs centered on his step-sister, Ami Nonomura. He is a junior high school student living with his family in Japan. Hiroshi is introduced as the step-brother of Ami, and the two share a close but ultimately taboo romantic and sexual relationship. His role in the narrative is largely defined by this relationship with Ami, which serves as a central emotional and dramatic conflict in the early episodes. After their mother discovers the incestuous affair, Hiroshi is sent away to study abroad in London, creating a significant emotional void in Ami's life. This separation becomes a key motivating factor for Ami's subsequent actions and choices, as she struggles with her lingering feelings for him. Later in the story, Hiroshi returns briefly, leading to a love triangle between himself, Ami, and her new lover Ryuji Kouno. His return reintroduces the unresolved tension from the earlier episodes and forces Ami to confront her past. Hiroshi's personality is not extensively detailed in the available material, but he is portrayed as a typical young male student who becomes entangled in a complex and socially forbidden relationship. His motivations appear rooted in genuine affection for Ami, though the consequences of their actions drive much of the plot. The character does not display any notable supernatural abilities or specialized skills; his significance lies entirely in his relational role within the Ami series. Over the course of the story, Hiroshi's development is limited to his shifting position as a source of longing and conflict in Ami's life, rather than undergoing significant personal growth himself.