1) An imaginary animal, probably resembling a weasel, but more cartoon like. They are said to be mischievous and charming creatures, which allows them to commit atrocities without repercussions.
2) An inanimate object or being on which to blame mishaps, or attribute misfortune
3) A person who takes advantage of, lies to, or in some way wrongs another, but has the charm and interpersonal skills to avoid punishment or retribution.