Some men enjoy masturbating during pegging. The naked appearance of actress Demi Moore in the advanced stage of pregnancy on the cover of Vanity Fair magazine in 1991 hentai movies marked the beginning of a period which has since seen pregnancy presented by celebrities as a glamorous state of living, while also creating a market for photographers to produce images of pregnant mothers, and for fashion stylists to introduce pregnancy styling to their business. They signal the presence of estrogen and the presence of sufficient fat stores for pregnancy and lactation. The precise definition of roles and self-identification is a common subject of debate, reflection, and discussion within the community. The current public acceptance of celebrities with sex tapes is speculated by Joe Levy, executive editor of Rolling Stone, to be due to the easy availability of pornography, as well as couples more commonly making their own gay cock tapes due to the prevalence of video cameras. It has since become popular enough with couples to be discussed during an episode of Sex and the City. As women, they face concerns separate from men. Group sex pornography features at least two men and two women , usually more, who all perform sex acts on each other. A study of the condom usage habits of New Zealand sex workers said that they offered various safe sex alternatives to vaginal sex to clients who refused to wear a condom. 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. Gay pornography is the representation of sexual activity between males. Arcane or occult pornography involves sexualized situations with an occult or magical tone or performers who costume themselves milf xxx in keeping with the theme, for example, a male performer dressed as a wizard. Medical pornography involves sexualized medical, often fake, including gynecological pelvic examinations, rectal examinations, and pelvic or gynecological ultrasounds.