Amane Fujimiya is a freshman who has been living by himself since starting high school. The most beautiful girl in his school, Mahiru Shiina, just happens to live in the apartment next door. The two of them don’t have any particular reason to speak to each other, but one day, when Mahiru is getting soaked in the rain, Amane lends her an umbrella. This is the beginning of their unusual relationship.
Unable to stand Amane’s slovenly lifestyle, Mahiru begins cooking for him, cleaning his apartment, and generally looking after him. Slowly, little by little, the two of them get to know each other. This is a sweet love story about a cute girl next door.