Sadism is defined as deriving pleasure directly from suffering or inflicting pain on a victim, or by seeing others undergo pain or discomfort (Baumeister & Campbell, 1999).
The personality characteristics of a sadist involve experiencing pleasure from the expense of others. The criteria for sadistic personality disorder include having maladaptive patterns of motivated behaviour and enduring and pervasive patterns of behaviour. The onset of sadistic personality disorder can be traced to adolescence and involve an inflexible behaviour pattern and physical cruelty or violence to show dominance in relationships. A sadist humiliates or demeans others, takes pleasure in the pain of others or animals, has lied to inflict pain on others, controls other people through fear and restricts the autonomy of their relationships. A sadist is said to be fascinated by violence and weapons, injury and torture (Hare, Cooke, Hart, 1999).
Rosen (2007) links the justified claim for retribution in those who openly seek revenge against others, with narcissism and sadism. French (2001) also links justified revenge with sadistic gratification. This link is also supported by Akhtar (2014) and Socarides (1966) through vindictiveness and lower level revenge fantasies.