Figuratively speaking, a person (usually woman) who "kills" other people with their looks, words or actions. Also known as a player or maneater, people nicknamed Assassin feel as if they are superior to the people around them and look for unsuspecting people for sexual, financial or social gain.
"See that girl over there? People call her Assassin...onelook and you're dead."
Dress up like a janitor to gain access to a seedy motel room. Hide out in the bathroom and wait for some pathetic John to call in the local hooker. After he pays for her, but before they start, run out of the bathroom and hit the John with a lead pipe while yelling, "sic semper tyrannis!" Fuck the whore, steal the John's wallet and car and make a dashing escape.