Haru, a schoolgirl bored by her ordinary routine, saves the life of an unusual cat and suddenly her world is transformed beyond anything she ever imagined. The Cat King rewards her good deed with a flurry of presents, including a very shocking proposal of marriage to his son! Haru embarks on an unexpected journey to the Kingdom of Cats where her eyes are opened to a whole other world.
A group of students lead normal lives and cope with normal predicaments, but all too often find themselves in abnormal situations.
The story is set in 1963 in Yokohama. Kokuriko Manor sits on a hill overlooking the harbour. A 16 year-old girl, Umi, lives in that house. Every morning she raises a signal flag facing the sea. The flag means “I pray for safe voyages”. A 17 year-old boy, Shun, always sees this flag from the sea as he rides a tugboat to school. Gradually the pair are drawn to each other but they are faced with a sudden trial. Even so, they keep going without running from facing the hardships of reality.