Dopptholamew "Doppy" Doppweiller is Carl's Planet Sheen counterpart. He resembles a green slug with Carl's face, and wears two pairs of glasses on his four eyes.
Like Carl, he can be overly worried about things and can easily feel insulted. Doppy is timid and dimwitted, but quickly makes friends with Sheen. He idolizes Dorkus, whom always tries to trick him into harming Sheen. His parents are incredibly overprotective, and that sort of rubbed of him. In his first major role, he mentioned his name was spelled D-o-p-p-tra-la-la-la-la-y. He also mentions that the "tra-la-la-la-la-" is silent but felt.