Kaho Hayakawa is a diligent high school student who has always been curious about romantic relationships but has never had a boyfriend. One day, she overhears her cheerful classmate Takumi Miura remarking that he wants a girlfriend—anyone would do. On impulse, Kaho steps forward and asks if she could be that person, and he accepts on the spot. Their arrangement begins as a trial relationship, an experiment of sorts. They exchange self-introduction resumes, share a list of things they want to experience as a couple, and start spending time together after school and on weekends. What begins as a tentative, almost contractual setup slowly transforms into something genuine. Kaho, who initially struggles to define her own feelings, grows more attracted to Takumi’s straightforward sincerity and kindness, while Takumi, who wanted a serious relationship rather than a casual fling, finds himself drawn to her earnestness and awkward charm. The narrative follows the small, everyday milestones of first love—first hand-holding, first shared meals, first misunderstandings—and the gradual, realistic process of two ordinary teenagers learning to trust and care for each other. Along the way, friends and classmates influence their dynamics, adding moments of gentle comedy and reflection, but the core of the story remains the quiet, heartfelt growth between Kaho and Takumi as they discover what it truly means to be in a relationship.