During a summer vacation when he was a child, Hayato made a promise with his dear (male) friend. Seven years later, Hayato transfers to a high school in the city and reunites with his childhood friend. She has become...a pure and beautiful girl! Haruki, known as the "unattainable beauty" of her class, smiles innocently at Hayato with a cheeky expression when they are alone, they exchange lunches in empty classrooms, and play games together at his house...but when Hayato teases her or treats her like a girl, she blushes. How adorable. Countryside and city, man and woman, mature mind and body. Some things have changed during their time apart, but some feelings and promises remain the same.