Haru is the younger daughter of kaihou kagurano and is highly passionate about tapioca world and its mascot, tapio-kun. her love for this world has negatively impacted her academic performance. to improve her grades and increase her chances of attending a good university, her father hires yukimura as a private tutor. despite being the daughter of an accomplished mathematics professor and frequently compared to her intelligent older sister, haru struggles with low self-confidence in her intellectual abilities due to her father's high expectations and others referring to her as "stupid." her personality is typical of a gyaru, characterized by informal speech and addressing yukimura as "yukipii." however, despite this reputation, haru demonstrates a capacity for learning and yukimura recognizes that her academic shortcomings may be partially due to her environment.