Not a direct answer to your question but Pieter Hintjens' Psychopath Code addresses this exact topic and offers ways to identify and contain such relationships.

Not a direct answer to your question but Pieter Hintjens' Psychopath Code addresses this exact topic and offers ways to identify and contain such relationships. http://hintjens.com/blog:_psychopaths http://hintjens.com/blog:_psychopaths