From the comments:
Narcissistic personality disorder (NPD) is a cluster B personality disorder defined as comprising a pervasive pattern of grandiosity (in fantasy or behavior), a constant need for admiration, and a lack of empathy (DSM-V).
Narcissists:
1. Have an exaggerated sense of self-importance
2. Have a sense of entitlement and require constant, excessive admiration
3. Expect to be recognized as superior even without achievements that warrant it
4. Exaggerate achievements and talents
5. Be preoccupied with fantasies about success, power, brilliance, beauty or the perfect mate
6. Believe they are superior and can only associate with equally special people
7. Monopolize conversations and belittle or look down on people they perceive as inferior
8. Expect special favors and unquestioning compliance with their expectations
9. Take advantage of others to get what they want
10. Have an inability or unwillingness to recognize the needs and feelings of others
11. Be envious of others and believe others envy them
12. Behave in an arrogant or haughty manner, coming across as conceited, boastful and pretentious
13. Insist on having the best of everything — for instance, the best car or office.
When criticized, NPD people can:
1. Become impatient or angry when they don't receive special treatment
2. Have significant interpersonal problems and easily feel slighted
3. React with rage or contempt and try to belittle the other person to make themselves appear superior
4. Have difficulty regulating emotions and behavior
5. Experience major problems dealing with stress and adapting to change
6. Feel depressed and moody because they fall short of perfection
7. Have secret feelings of insecurity, shame, vulnerability and humiliation.
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They "feed" on other people, in any way imaginable...sexually, financially, emotionally, whatever way they can push people's boundaries to benefit them...because it's always about them.