Sadists often seek out masochists as sexual partners. The sexual arousal in sadism is directly related to the suffering of the other person. Some acts involve actual physical violence, including cutting, burning, or beating. Other acts involve domination, such as making the other person crawl or keeping him or her in a cage. Still other acts involve humiliation.
Sexual sadism is much more common in males.
Heterosexual masochists usually have difficulty in finding sadistic female partners. However, the incidence in females appears to be on the rise. Most sadists begin having fantasies about these activities in childhood. They usually begin experimenting with partners by early adulthood. Some people may engage in sadistic acts with consenting partners for many years without ever actually injuring anyone.