Haru is a young schoolgirl full of doubts who cannot find her place among others. Her life is suddenly turned upside down when, on her way back from school, she saves the life of a cat in danger of being run over by a truck. It’s not just any cat. He talks, stands on his hind legs and is called Loon: he is the prince of the cat kingdom. The felines are thus chalked up to Haru. The next day, they shower her with gifts and their king invites her to his castle to thank her. The monarch wants her to marry his heir.