Dominance and submission (also called D/s) is a set of behaviors, customs, and rituals involving the submission of one person to another in an erotic episode or lifestyle. It is a subset of BDSM. This form of sexual contact and pleasure has been shown to please a minority of people. Physical contact is not necessary, and D/s can be conducted anonymously over the telephone, email, or other messaging systems. In other cases, it can be intensely physical, sometimes crossing into sadomasochism. In D/s, both parties take pleasure or erotic enjoyment from either dominating or being dominated. Those who take the superior position are called dominants—Doms (regardless of gender) or Dommes (female)—while those who take the subordinate position are called submissive, or subs. A switch is an individual who plays either role. Two switches together may negotiate and exchange roles several times in a session. The term dominatrix usually refers to a female sex worker who dominates others for pay. History The dominant–submissive relationship fits within the overarching term BDSM and its lifestyle. BDSM stands for "bondage and discipline" (B&D), "dominant and submissive" (D&S), and "sadism and masochism" (S&M). Many misconceptions of this relationship and its associated activities come from the fact that early theorists conceptualized that sadomasochism and BDSM behavior were a symptom of psychopathology. It was thought that people who participated in this type of sexual play disregarded safety and consent, which influenced the diagnosis, classification, and perception of this type of relationship. These misconceptions of all participants of BDSM having disordered tendencies have related to the definition and criteria for sadomasochism in the DSM-5. Therefore, many in the BDSM community do not fit the criteria. It is possible that this community of BDSM participants was formed in the early 18th century, and maybe even before. For example, the dominant–submissive partnership has been shown in early versions of the Kama Sutra. Not only is it shown in literature but also in the actions of ancient rulers that would participate in sexually sadistic torture, role play, and finally the assertion of their dominance over subjects. Their actions show severe sadomasochism as well as the early-onset behaviors of the community. The relationship between a dominant and submissive revolves around consent and guidelines. Within the world of BDSM, consent is a core focus and requirement because it is what separates sexual sadism from coercive sexual sadism disorder in the DSM-5. Sexual sadism