Marina is a light-tan fish who has light brown hair with pink lips. She is also seen wearing her Hotdog on a String uniform, which includes a green, light-purple, and white-striped shirt and a bucket that says "Hot Dog" on it.
Marina is first seen once Pearl calls her, asking if she wants to hang out. Marina declines the offer, saying she is at work. She then serves a customer a Hotdog on a String with extra string, much to her disgust.
A little later, Pearl visits Marina at Hotdog on a String in her first attempt to get a job. Marina calls out to her manager, Mr. Pepalino, and tries to help Pearl get through the door but is unsuccessful. Marina is not seen again until later after she, Nocturna, and Nixie are all having lunch and invite Pearl to join them.
However, after Pearl tells everyone that she is working at Grandma's Apron, Marina, Nocturna, and Nixie all make fun of her for working at an "old person's" store. They then confront Pearl later at her job to make fun of her more but Beatrice manages to beat them up. Marina, Nocturna, and Nixie all apologize to Pearl, saying it is just awkward for her to be a "grandma."