The user possesses an incredible and innate understanding/knowledge of psychology and can use it for various purposes, often by changing the perception or behavior of others through underhanded, deceptive, or even abusive tactics.
More benevolent users may use it to help those with mental or emotional problems, while the more malevolent users may use it to manipulate others into doing their bidding, or even drive some to acts of murder or suicide.
Batman (DC Comics) is a master at understanding the scarred psyche's of his adversaries..
Hugo Strange (DC Comics) is a formidable enemy of Batman's, who is privy to the dark knight's secret identity.
Karnak (Marvel) of the Inhumans can utilize his abilities to find the faults of anything, To this end he can also expertly deduce the various aspects of another persons psychology to a tee, finding the faults to their personalities to better gain leverage over his opponents.
While Dr. Hannibal Lecter is clearly psychotic, he's fully aware of this and is still a genius in psychotherapy.
Nate Ford's (Leverage) years as an insurance fraud investigator gives him an understanding of how his targets will react to certain situations.
Angel/Angelus (Buffy the Vampire Slayer) displays incredible skill in manipulating others' psyches and emotional states.
Charlie Bartlett (Charlie Bartlett) has a natural gift for understanding psychology.
Yui (Sword Art Online) was created to monitor and take care of the mental health of the Sword Art Online players.
The half demon Naraku (InuYasha) was shown to be a master at manipulating demons and humans alike. Throughout the series, he manipulated many people and demons to get what he wanted without getting his own hands dirty.
Akainu (One Piece) is an excellent manipulator, using Squard and Ace's loyalty to Whitebeard to his advantage and successfully killing the latter by doing so.
Doflamingo (One Piece) used Luffy's late brother's Devil Fruit to draw him, his crew, and Law to Dressrosa to the point where, while using the Birdcage, he turn some major of the citizens and criminals against them and each other using fear and greed.
Spectra once posed as Casper High's School counselor, she used this to make others feel miserable by using their future, looks and confidence.
Alejandro (Total Drama World Tour) uses his charms to manipulate others, including animals, making him untrustworthy.
Hannibal Roy Bean (Xiaolin Showdown)
Neyla could perform a high level of psychological warfare; she could charm anyone before betraying them, as she betrayed the Cooper Gang, Interpol and the Klaww Gang.