Hugo Ohira, director of marketing for Silvercash, rhetorically asks Who does not like spewing their load on a pretty young face? As of 2013, little analysis of this paraphilia has been reported in medical literature. Participants usually derive pleasure from this, even though many of the practices—such as inflicting pain or humiliation or being restrained—would be unpleasant under other circumstances. For other diaper fetishists, simply wearing a diaper, the bulking feeling and crinkling sounds associated with it, is enough to cause the fetishist a form of erotic pleasure or sexual arousal. The person receiving anilingus is regarded as the passive partner in the act, and the person performing anilingus is the active partner. There is also some evidence that pornography can be used to treat voyeurism. It is sometimes described as a sexual fantasy, big tit milf by women or men, depicting an exhibitionist or physique worship scenario. Performers are usually clean-shaven, thinner and more effeminate than ones in mainstream gay pornography. Each participant may engage in any type of sex acts with one or both of the others, such as vaginal, anal or oral sex or mutual masturbation. Masturbation has been depicted in art since prehistoric times and is mentioned and discussed in very early writings. Sexologist Alfred Kind suggested that the buttocks is the primary sexual presentation site in primates. In pornography, depictions of lesbian sex form gay fuck a popular subgenre, directed toward a male heterosexual and female homosexual audience. When he is in position the cover is closed. Simultaneous penetration of the mouth and either the vagina or anus. Well-known female porn stars who expressed their pleasure in pegging their male partners include Taylor Wane, Debi Diamond, Brittany Andrews, and Monique Covét. Related 3d hentai genres include: Amateur pornography originally referred only to pornography produced by amateurs but now also includes professionally made pornography designed to appear as if it were amateur.