The consent and compliance for a sadomasochistic situation can be granted only by people who can judge the potential results. Creampie scenes depart from heterosexual pornographic convention in favor of a depiction that more closely mimics sexual intercourse as performed in ordinary life; they have been called the counterimage of facials. Mammary intercourse is said by Alex Comfort to produce mutual orgasm in women with sensitive breasts , and it was one of the nine substitute exercises for penetrative sexual activities, as detailed in the Paradis Charnels of 1903. This style of filming is in contrast to having a separate, third-person camera crew filming all the action. Pregnancy fetishism is a context where pregnancy is seen by individuals or cultures as an erotic phenomenon. The term discipline describes psychological restraining, with the use of rules and punishment to control overt behavior. Originating in Japan in the 1980s, the genre subsequently spread to North America and Europe, and crossed over into gay pornography. Urolagnia is a form of salirophilia in which sexual excitement is associated with the sight or thought of urine or urination. A pornographic work is characterized as hardcore if it has any hardcore content, no matter how small. As of 2013, little analysis of this paraphilia gay hentai has been reported in medical literature. Voyeurism: Seeing another urinate without the person knowledge either through video taping by a hidden camera, or by lurking in locations where porn milf people are urinating or are likely to have an urge to urinate. The arousal from being desperate comes from the sensation of having a full bladder. The scenario is a genre of erotica, which on the internet is sometimes abbreviated to CMNF, and may involve sexual and nonsexual erotic scenarios. Starting with erotic stories and woodblock prints from before the 20th century, Japanese pornography evolved into distinct subcategories with the media that in addition of pornographic videos and magazines featuring live actors, gay fuck there is exist categories of pornographic manga , pornographic computer games , and pornographic anime .