"Serial killers tend to be white, heterosexual males in their twenties and thirties who are sexually dysfunctional and have low self-esteem. Their methodical rampages are almost always sexual in nature. Their killings are usually part of an elaborate fantasy that builds to a climax at the moment of their murderous outburst. Serial killers generally murder strangers with cooling off periods between each crime. Many enjoy cannibalism, necrophilia and keep trophy-like body parts as mementos of their work."