Hisui Nonaka is a character from the visual novel and anime series 'Tsukihime.' She is a maid working at the Tohno Mansion and serves as one of the supporting characters. Known for her subdued and quiet demeanor, Hisui is dedicated to her duties and deeply cares for the well-being of others. Despite her reserved nature, she has a deep bond with her twin sister, Kohaku. Her character adds a layer of warmth and emotional depth to the series, often acting as a grounding presence amidst the supernatural events surrounding the Tohno family.