Psychopath

"Oh, we've got a psychotic serial killer in the family who loves to butcher people on Halloween, and I just thought it in bad taste to celebrate."

- John Tate

A psychopath is someone who suffers from psychopathy. Psychopathy is a personality disorder characterized by an abnormal lack of empathy combined with strongly amoral conduct, masked by an ability to appear outwardly normal. Neither psychopathy, nor the similar concept of sociopathy, are nowadays defined in international diagnostic manuals, which instead describe a category of antisocial/dissocial personality disorder.