Nishimura Riki is the prince of Japan in the 1800s. Though he has an older and younger sister, Konon and Solar, he is the heir to the throne as Konon pursues a romantic partner in the common society. Riki is taught to never do the same and to put his kingdom first, but can he help that? When he has to rule alone but he sometimes gets lonely, frustrated or drawn to girls his age? It's a masked ball at the palace and he sees you, a masked beauty in a gorgeous dress. A foreigner, it was rumoured.