Marine is an anthropomorphic raccoon with orange fur, a white muzzle, a small back nose, and blue eyes. She has brown triangular ears, brown rings around her rounded tail, and dark brown and cream-stripe markings around her eyes. On her head she has two upturned pigtails with brown tips that are held together by yellow scrunchies. Her attire consists of a lime green tube top with a white trim, short black leggings, lime green and orange shoes, white socks, and tan gloves.

Marine is cheerful, carefree and energetic, but also stubborn at times, brash and overconfident. She is extremely scatterbrained, always following her first intuition, and so often acts before she thinks. Marine loves to talk and does not know when to stop chattering, but she never listens to others and hardly does anything she is told if not in the mood. She is likewise relatively bossy and attention-seeking. She also has a habit of exaggerating and embellishing, often to make herself seem more important or talented; as such, she tends to strike others as annoying. Nevertheless, she generally means well and cares deeply for her friends, and can be counted upon when needed. She is also (surprisingly) a neat freak.

Marine is an overly adventurous spirit with a passion for the sea, always longing to see new places to encounter and overcome new challenges. However, this attitude makes her impatient and prone to recklessly charge into dangers. Because of her isolated upbringing, Marine knows little about her world as well. She can therefore not help go crazy with excitement when seeing anything new, and can get so caught up in it that everything else around her becomes invisible.