The story follows Mihonosuke Tachibana, A To-Be royal bride in the large and thriving Island kingdom, Havarleshica (Have-are-lesh-shi-Ka). As the eldest daughter of the King and Queen, Mihonosuke (Miho for short) is betrothed to an English Prince named Toffee whom, quite frankly, hate each other. On their wedding day, a huge waterspout occurs and causes the whole island to sink to the ocean floor. Miho, Toffee, Shaniia (Miho's Lady in Waiting), Olivia (Miho's younger sister), and multiple other islanders escape due to the help of a young sailor named Darvinan and his death/blind father Marvin. Together, they find themselves arriving at yet another small island with a population of a thousand. A thousand sea monsters.