Riddle: A woman meets a man at the funeral of one of her relatives and falls madly in love with him. A week later she killed her sister. Why did she kill her sister?
Answer: She killed her sister so that she could see the man again. Most people will say that she killed her sister because it was either her husband or boyfriend. They use this to test people and if you get it right, you are said to think like a psychopath.