Haruka Hasebe, a student initially in Class D at Tokyo Metropolitan Advanced Nurturing School, has waist-length blue hair, orange eyes, and a mole beneath her left eye. Her average height and well-endowed physique are often noted by classmates. She typically wears her school uniform with the top button undone and the tie loosened. Academically average, her official evaluations rate her academic ability and physical skills as D, intellect and judgment as C+, and cooperativeness as D. An introvert with perceptiveness, she avoids social interactions with strangers, particularly boys who focus on her physique. However, with close friends like the Ayanokōji Group, she becomes talkative and playful, assigning affectionate nicknames like "Kiyopon" or "Ayanon" to Kiyotaka Ayanokōji. She exhibits a teasing demeanor but displays firmness in serious situations, confronting Kiyotaka about withheld truths. She experienced unrequited feelings for an athletic upperclassman in middle school but took no action. In high school, she developed an interest in Kiyotaka after observing his physical prowess during the sports festival relay. She tested her feelings by spending time with him but suppressed them upon recognizing her friend Airi Sakura's affection for him, choosing instead to support Airi's romantic efforts. Haruka actively encouraged Airi to become more confident, coordinating matching swimsuits to attract Kiyotaka's attention and directly questioning him about his feelings for Airi. When Airi faced expulsion due to low academic performance in the Unanimous Vote Special Exam, Haruka volunteered to be expelled in her place, though this was rejected. Airi's expulsion triggered a profound reaction: Haruka took a week-long absence from school and adopted a vengeful stance against Kiyotaka and Suzune Horikita, blaming them for the outcome. She planned to drop out to reunite with Airi, disregarding the consequences for her class. This phase culminated when Kiyotaka delivered a parting gift from Airi—a maid dress. Haruka initially interpreted it as a symbol of Airi's hatred. Kushida Kikyō intervened, revealing Airi's new idol activities under the name "Shizuku" and criticizing Haruka's motivation. Both Kushida and Kiyotaka asserted that Haruka's support stemmed from a desire to feel superior by helping someone weaker, not genuine concern. This confrontation, coupled with evidence of Airi's resilience, prompted Haruka to abandon her dropout plans. She refocused on graduating from Class A to reunite with Airi proudly and participated in the cultural festival as a maid, fulfilling a commitment linked to Airi's gift. Beyond these relationships, she maintained skepticism toward Honami Ichinose's perceived perfection, suspecting hidden flaws. She collaborated with Akito Miyake during her vengeful phase before his intervention helped her reconsider her actions.