Kanojo no Ai ga Omosugite Tsurai

Mitsuya Haruyoshi is a devout Christian high school student whose life has been shaped by his family's turbulent past. After his mother's infidelity, his father became a priest and now expects Haruyoshi to follow the same path. Determined to honor his father's wishes, the young man strictly avoids all forms of lust and worldly desire, dedicating himself to a life of religious discipline. His carefully guarded routine is upended when Sonoda Hanako, his female childhood friend and the daughter of a local sweetshop owner who attends the same school, invites him to her home. Upon arriving, Haruyoshi discovers that her family has drastically shifted their business model—transitioning from selling sweets to running a sex shop in order to survive the economic impact of declining birthrates. Hanako then confronts him with a long-forgotten childhood promise to marry her, presenting a makeshift ring he once crafted for her out of aluminum foil. Armed with her own clever interpretation of his faith, she points out that Christians are only permitted to engage in intimate acts within marriage. By this logic, she reasons, if she initiates anything lewd with him, he will have no choice but to fulfill his childhood vow and become her husband.