A person that is utterly repulsive. Their personal qualities are comparable to that of a
sewage tanks. They are filled with an
overload of disgust and can be considered just a volume of waste to the rest of the surrounding world.
Jake cheated on his girlfriend, stole from his grandma, and
stomped on a squirrel. He is a Sewie.
Sarah: "I caught Jake cheating on me again"
Sarah's friend: "Ew, you need to dump that Sewie."
