The story centers on Sakuraba Aoto, a plain high school student who values his peaceful, solitary life. His world is disrupted by the overwhelmingly popular and perfect Yuunagi Shizuno, a beautiful, intelligent, and kind girl admired by everyone. Despite her popularity, Aoto feels no envy and is content with his own life, preferring his own company. However, Shizuno confesses her feelings to Aoto and, through her persistence, becomes his girlfriend under specific conditions: Aoto doesn't have to love her back, and she cannot be possessive.
Aoto struggles with this arrangement, constantly reminding Shizuno of their agreement and her promise not to act suspiciously, like waving at him from afar. He fears she will break their pact, leading to their immediate breakup. Shizuno, despite her outward perfection, is clearly smitten and prone to jealousy and anxiety, often acting impulsively due to her strong feelings for Aoto, who remains emotionally detached.
Aoto's friend, Seo Kazuma, constantly urges him to date and criticizes him for not utilizing his popularity, unaware of Aoto's secret relationship. Meanwhile, Aoto develops a friendship with Naruse, a kind and book-loving girl who asks him out to a bookstore. This date sparks intense jealousy in Shizuno, who, with the help of her pragmatic best friend Shirato Kasumi, decides to secretly follow Aoto and Naruse. During their "date," Aoto and Naruse discuss books and plan future outings, while Shizuno and Kasumi observe from a distance. Shizuno becomes increasingly anxious, especially when she witnesses Naruse seemingly confessing to Aoto.
Shizuno, distraught, confronts Aoto, confessing her jealousy and fear of losing him. Aoto, though finding her behavior problematic, is also affected by her distress. He reassures her that he rejected Naruse's confession and that his actions are not indicative of romantic interest in Naruse. He also reveals that his initial reason for agreeing to date Shizuno was partly due to her persistence and a desire to avoid causing her further distress, despite his lack of romantic feelings.
Later, Shizuno proposes a compromise: they can be "friends" at school, allowing them more interaction without breaking their agreement. Aoto initially rejects this, citing the unnaturalness of their sudden friendship given their different social circles. However, Shizuno reveals her true motivation: to publicly establish their relationship as "friends" to deter other girls, particularly Naruse, from approaching Aoto. Aoto, seeing Shizuno's desperation and realizing her deep affection for him, eventually agrees to her proposal, though he remains cautious about her possessive tendencies. The narrative concludes with Shizuno's overwhelming joy and Aoto's resigned acceptance of her intense feelings, hinting at future challenges in their unconventional relationship. The story also flashes back to the moment Shizuno fell for Aoto: during a movie outing, when he selflessly helped her after she spilled popcorn, without being fazed by her disguised appearance.
