Pantyhose/Tights/Stockings pornography involves women or men dressed in pantyhose, tights, or stockings. The resulting consent and understanding is occasionally summarized in a written contract, which is an agreement of what can and cannot take place. The loose and direct camera work often includes tight shots of the genitalia, unlike some traditional porn. The industry generally refers to such films as adult films, which is part of adult entertainment. It has since become popular enough with couples to be discussed during an episode of Sex and the City. Being forced to wear diapers as a form of humiliation is sometimes a behavior encountered in sexual masochism. As the prostate is touch-sensitive, some directly stimulate it using a well-lubricated finger or dildo inserted through the anus into the rectum. Patricia Hill Collins, an African-American writer, theorizes that this is derived from a stereotype that those of black descent are promiscuous, and their buttocks are objectified by porn as a result. During anal sex, male pleasure can be particularly derived from the prostate, which can lead to an orgasm and ejaculation. For some people, non-penetrative porn milf sex is the primary sexual activity of choice above all others. Most bisexual porn is made by small production companies rather than the major studios. Gay pornography is the representation of sexual activity between males. Low et al. Milking pornography features lactating women gay fuck being milked or milking hentai sex themselves . No causal relationship is known between masturbation and any form of mental or physical disorder. Such works have also often been subject to censorship and other legal restraints to publication, display or possession. The study also found that participants reacted positively to a much wider range of figures than a control group, even rating emaciated figures higher. The preference could be barefoot, high-heels, flip flops, and so on, depending on the fetishist. Following World War II, during a period of social repression when governments actively persecuted homosexuals, women developed networks to socialize with and educate each other.