Doug Rattman

Description
Doug Rattman is a reoccurring unseen character in the Portal game series, as well as the protagonist of the Portal 2 tie-in comic, Lab Ratt. He is the focus of the first episode of Season 2, when Mullet Mike reviews the game Portal 2 and tries to decipher an audio file believed to be Doug Rattman's voice.

Plot
During the first episode of Season 4, Mullet Mike reveals that Doug Rattman moved into his attic, and made an mild appearance in Season 4 Episode 14 making noise till Mike poked the attic with a broom, where he remains until the pilot of Season 7.