Sōichirō Yabe works as editor to renowned erotic novelist Hanasaki Horie, Ao's father. He is an adult male with neck-length black hair, gray eyes, and a professional demeanor, typically wearing glasses and suits during his work visits to the Horie residence. These frequent visits to manage Hanasaki's publishing affairs have fostered a growing familiarity between Yabe and Ao over time. Yabe perceives his repeated interactions grant him a deeper understanding of Ao than her classmates possess. His role centers on professional collaboration with Hanasaki, though his presence occasionally intersects with Ao's personal life during household encounters. Across the series' manga, anime, and related media, Yabe's character remains consistent; his contributions stay confined to his professional capacity as Hanasaki's editor, with no expansion on his motivations, history, or personal growth.