Conway the Contaminationist is a revolting pilot who claims to have discovered the means to a better, longer life. His only centric appearance was in his eponymous episode.
Conway appears to be a very old man, as stated by himself, about 193 years old. His eyes are very bulbous and his skin is a greyish green (possibly caked on mud) with green bulbs all over it, skinny limbs and large head. He doesn't seem to have teeth anymore and his tongue is a lemon green. He wears a tattered aviator coat with a fur collar and sleeves and a pink scarf as tattered as the coat, along with black pants and black shoes. Whenever he talks, small clouds of dust come out of his mouth.
Conway is an antagonist that arguably doesn't actually mean any harm, in fact, he wants to make people's lives better. He believes surrounding oneself in filth and grime is actually beneficial to the health, which may or may not be true as a jar of putrid sludge revives him like smellingsalt and he claims to be 193 years old, but Eustace and Muriel become emaciated and weak when their lives become disgusting. He can pilot a plane, which he uses to advertise his way of life.
Conway is a pilot, and from his plane he passes out flyers to promote the lifestyle of filth. He insists that years of living in trash and grime has promoted his long life and good health. Sludge from gutters and feet always makes him feel better. However, when he imposes this on the Bagges, they get sicker and sicker by the day, until Courage has enough and vacuums both Conway and his beloved filth into a plastic vacuum bag. Conway is happy in his new home, and never bothers the Bagges again.