Rat (debut: Dec. 31, 2001) is a megalomaniacal rat on Pearls Before Swine. He is frequently critical of the strip's style and artwork as well as the other characters in the strip and all living things. Often self-employed, most of his businesses involve either punishing or defrauding people for their ignorance, much in the same vein as Dogbert, though with a darker humor.
Rat is the most insensitive character in the strip, except when it comes to his love for Pig's sister Farina; he also seems to feel some genuine friendship toward Pig himself, although this hardly gives Pig any immunity from Rat's insults. Rat's interactions with others are typically sarcastic, condescending, insulting and sometimes violent, particularly when dealing with what he considers to be exceptionally annoying people (i.e. virtually everyone) and their habits. Rat frequently breaks the fourth wall to berate his creator on his jokes, artwork or general content of the strip itself.