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 infli of pain on another person. the term was ed by the te 19th-tury german psychologist richard von krafft-ebing in refereo the marquis de sade, an 18th-tury frenan who icled his own such practices. sadism is often lio masochism (q.v.), in which sexual arousal results from receiving pain, and many individuals respond iher 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 aent of sadistic violence may vary siderably, from infli of mild pain in otherwise harmless love py to extreme brutality, sometimes leading to serious injury or death. the satisfa of the sadist may result not from inflig 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 bees 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。性表达也许局限于某种程度的暴力，但有时攻击性占有欲太强，而导致极端的暴力倾向。施虐可能是某些暴力罪案发生的因素，特别是强奸和谋杀。
以xanthe而言，她在里面就塑造了一对和skinner/mulder完全对应的主奴，以强制调教的方式让他的奴隶变得柔软而顺从。而在里面更是身体力行了一回，里面的劳伦斯就是个典型的施虐狂，mulder的不合作显然让他得到了更大的乐趣，征服的乐趣。而一旦被打破，驯服的奴隶反而会让他失去胃口。他最后放mulder走，也是出于不愿mulder被彻底打破而变得柔顺的心态。所以，真正的施虐狂，也许并不见得很享受完全服从的奴隶，但他们确实是s，也确实能从征服中获得乐趣。但是，他们并不是大众所能接受的那种主奴关系中的主人，那种视照料m的需求为己任的主人。