Alissa, the librarian at the Royal Library, one day discovers a diary that has a special magic. After she writes her name in the diary, she meets a boy in an unfamiliar place who introduces himself as Louis. Alissa, who thought she was just a world in a diary anyway, becomes friends with young Louis and she spends her time with him. Meanwhile, the young king who did not get married put the whole country in trouble. To finally select a queen, unmarried noble women from all over the country are invited to a ball. However, at the ball that Alissa nonchalantly attended, confident that nothing would happen, the king strangely took an interest in her.
