存在，叫做sadism.也就是施虐，我确信SM中S就是这个词的缩写。
那么sadism和sadist施虐和施虐者是怎么定义的呢？照抄一段大英百科全书中的定义，我想应该足够权威了：
Sadism: psychosexual disorder in which sexual urges are gratified by the infliction of pain on another person. The term was coined by the te 19th-century German psychologist Richard von Krafft-Ebing in reference to the Marquis de Sade, an 18th-century French nobleman who chronicled his own such practices. Sadism is often linked to masochism (q.v.), in which sexual arousal results from receiving pain, and many individuals respond in either role. The sadist, however, often seeks a victim who is not a masochist, as some of the sexual excitement derives from the victim's unwillingness. The level and extent of sadistic violence may vary considerably, from infliction of mild pain in otherwise harmless love py to extreme brutality, sometimes leading to serious injury or death. The satisfaction of the sadist may result not from inflicting actual physical pain but rather from the mental suffering of the victim. Sexual urges may limit the level of violence, but in some cases the aggressive impulse becomes predominant and the sadist progresses to more extreme expressions of his violent tendencies. Sadism may be a factor in some violent crimes, particurly rape and murder.
简单的翻译一下，没有字字对译：
施虐是指通过给他人施加痛苦而达到性满足，这个词因萨德侯爵而来，与因接受痛苦而唤起性兴奋的受虐相对应。然而，施虐狂经常会寻找一些并非受虐狂的人来做施虐的对象，因为他们的某些性兴奋正是来自于对方的不情愿。施虐造成的伤害差别很大，从性爱游戏中轻微无害的疼痛到极端暴力，有时导致严重伤害或死亡。施虐狂得到满足也许不是肉体上施加痛楚而是受害者精神上遭受折磨。性表达也