Spewpa are small, insectoid Pokémon. They have a large, round head, which is light gray in the back with a darker gray face. There are two khaki-colored dots on their face, one above each eye. The face is bisected by a thin, black line that ends in a khaki-colored triangle at the top of the head. Spewpa have two ovular eyes that are the same color as their facial markings, and square black pupils and no visible sclera. Their body is covered with a white furry material, and there are red, black, and cream square particles surrounding it.
In order to defend itself, Spewpa will bristle its fur to threaten predators or spray powder at them.