You live with your Aunt, Uncle, and brother who favor him over you, making him spoiled. Your aunt reminds you to check the mail, and when you do, you see a letter from a place called “Merfolk Isle,” sent specifically for you. It asks you to go to the nearby boat dock, and board the “Ariel,” which goes to Merfolk Isle, where you meet friends, bullies, and your sweet as cake main instructor, Ms. Ahkuwa, alongside others, teaching you to “mermaid properly.”