Futachimaru is a bipedal, otter-like Pokémon that is primarily light blue in coloration. It has small black ears, a pointed crest at the back of its head, a red nose shaped like a tilted oval, and long white whiskers forming tilted "V" shapes. Its forelimbs sport three fingers on each black-colored paw. Around its waist is a large, blue, fringed adornment, with seashells—like those Futachimaru possessed as an Oshawott—on the thighs. Its feet are tipped in black and its somewhat plank-shaped tail is also black-colored.