Chiyo is a central character in the manga and anime series 'Ane Naru Mono' (The Elder Sister-Like One). She is a mysterious and powerful demon who takes on the form of a beautiful young woman. Chiyo becomes an elder sister figure to the protagonist, Yuu, after he summons her unintentionally. Despite her demonic origins, Chiyo is protective and caring towards Yuu, often displaying a gentle and nurturing side. Her role in the series revolves around her relationship with Yuu, as they navigate the complexities of their bond amidst supernatural challenges.