The Hat Guy, whose real name is never given, is a recurring character in Randal Munroe's xkcd webcomic. In the strips that feature him, he is often seen as a sadistical jerk, purposely causing emotional pain to those around him, and sometimes lowering their self-esteem, especailly to those that he thinks deserve it. He once found a car that was parked over two spaces, and he promptly disassembled it with a blowtorch so he could fit his car into one of them. He also like causing subtler pain to his targets, such as making women on the subway think he's interested in them, and then rolling his eyes to crush their ego.
His subway antics once back fired on him, when he met an equally sadistic, unnamed woman on the subway. After trying to out-hurt each other for a long time, the two started a relationship. Their dates involve murdering people and hiding the evidence.