Jonny Belt Creator, Executive Producer Robert Scull Creator, Executive Producer Jacob Bertrand Gil (Speaking) Voice Teddy Walsh Gil (Singing) Voice Bailey Gambertoglio Molly (Speaking) Voice Brianna Gentilella Molly (Singing) Voice Tori Feinstein Oona Voice Tino Insana Mr. Grouper (Speaking) Voice Chris Phillips Mr. Grouper (Singing) Voice Jet Jurgensmeyer Nonny Voice Grace Kaufman Deema Voice Mia Vavassuer Little Fish Voice Marleik "Mar Mar" Walker Goby Voice Zachary Gordon Gil Voice Angelina Wahler Deema (Speaking) Voice Selena Gonzalez Deema (Singing) Voice Reyna Shaskan Oona Voice Jelani Imani Goby (Speaking) Voice Christopher Borger Goby (Singing) Voice Eamon Pirruccello Nonny Voice Skai Jackson Little Fish Voice Janice Burgess Co-Executive Producer