Cala Maria has a physical appearance reminiscent of a typical humanoid female character. She is a giant, tall, slender mermaid with fairly wide hips and a small waist. She has pale skin, a small button-nose, and two scar-like markings on the bicep of her left arm (though how or why she got them is unknown, but it could be a reminiscent of eel bite marks).

Cala has big, pale turquoise eyes with sea-green eyelids and three short, black, triangular eye-lashes each.