A threesome is also depicted with one woman and two men who all perform sex acts on each other . These actors often play the top roles but this is not always the case, such as with Kristen Bjorn gay boy porn and some Bel Ami models. The loose and direct camera work often includes tight shots of the genitalia, unlike some traditional porn. Smotherboxes are usually custom made pieces of furniture that may have a special significance for their users. Some aspects of the research community distinguish between nude milfs female ejaculation and what is colloquially known as squirting or gushing. The primary subjects of pornographic depictions are pornographic models, who pose for still photographs, and pornographic actors or porn stars, who perform in pornographic films. The term BDSM dates back to 1969; however, the origin of the term BDSM is unclear and is believed to have been formed either from joining the term B&D with S&M , or as a compound initialism from B&D, D&S , and S&M. Locks may be used to emphasize the submissive position or the submissive hands may be fastened above his head to the box. Ass to mouth is a slang term primarily used to describe the withdrawal of a penis from the receptive partner anus followed by the immediate insertion into the receptive partner mouth. Some masturbate only using pressure applied to the clitoris without direct contact, for example by pressing the palm or ball of the hand against underwear or other clothing. The precise definition of roles and self-identification is a common subject of debate, reflection, and discussion within the community. The term breast fetishism is also used to refer to cultural attention to female breasts and the sexuality they represent, with debate continuing as to whether the modern widespread fascination with breasts among heterosexual males in western societies is a sexual fetish. Reality pornography is a genre of pornography where staged scenes, usually shot in cinéma vérité fashion, set up hentai movies and precede sexual encounters.