Triolism is a term that is used in the field of medicine, to refer to a type of paraphilia, which is based on the need that a person has to watch their partner have sex with one or more individuals at the same time whether they are of the same sex or the opposite sex. For an individual who presents this type of impulse, it is necessary to be able to observe other people having sexual relations in order to achieve sexual pleasure, and it is very likely that she will be incorporated into the group that she is observing. This is one of the reasons why the porn industry is based on the idea of ​​generating sexual pleasure for people through erotic images.

When an individual exhibits this type of behavior, it is very likely that he or she has a sensation of pleasure when being present in a sexual act, whether said action is live or has been captured in photographs or on video. In the same way, said person can feel the same pleasure if he observes other individuals. One of the forms of triolism that occurs with some frequency is to observe the couple when they are having sexual relations with a third person, which can be seen as a form of candaulism, which refers to the pleasure of forcing the couple to have relations with third parties or, failing that, to undress in front of others, as well as to show third parties any sexual situation carried out by the couple and that has been reflected in photographs or videos.

There are experts who affirm that troilism originated as a result of voyeurism, a paraphilia that is characterized by the fact that people tend to feel pleasure when observing a figure that shows nudity, that is, it is not necessary to engage in a sexual act.

Triolism is often seen as brazen behavior that is even considered spontaneous and that for some is something dirty that usurps the instincts of sexuality. There are people who even have a careless attitude, who may feel pleasure in not being cautious in this regard, but on many occasions it is only a mask that seeks to hide the feeling of guilt for such acts.