Miyabi Kannagi is a key character in the anime series 'Kono Naka ni Hitori, Imouto ga Iru!' She is a classmate of the protagonist, Shougo Mikadono, and is known for her energetic and somewhat mischievous personality. Despite her often playful demeanor, she harbors deep feelings for Shougo and is one of the contenders who might be his half-sister. Miyabi's character adds a layer of complexity to the story, as she balances her romantic interests with the mystery surrounding her true identity in relation to Shougo.