Such grounds and even the definition of pornography have differed in various historical, cultural, and national contexts. Reading or viewing pornography, sexual fantasy or other erotic stimuli may lead to a desire for sexual release such as by masturbation. People may experience pleasure from anal sex by stimulation of the anal nerve endings, and orgasm may be achieved through anal penetration – by indirect stimulation of the prostate in men, indirect clitoral/G-spot stimulation in women, and associated sensory nerves . The term gay twink porn 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. Clothed male, naked female is one-sided female nudity in which one or more females are nude while one or more men are clothed. Testosterone discourages fat storage in these areas. Coprophilia , also called scatophilia or scat , is the paraphilia involving sexual arousal and pleasure from feces. The term milf xxx breast 3d hentai porn 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 hentai porn among heterosexual males in western societies is a sexual fetish. Point of view pornography is adult entertainment filmed to look as if the watcher were experiencing the sex act themselves. Works in this genre may be considered adult for any number of reasons. Erotic spankings are commonly combined with other forms of sexual foreplay. Unlike the usual power neutral relationships and play styles commonly followed by couples, activities and relationships within a BDSM context are often characterized by the participants taking on complementary, but unequal roles; thus, the idea of informed consent of both the partners becomes essential. As women, they face concerns separate from men. Snowballing or snowdropping is the human sexual practice in which one person takes someone else semen into his or her mouth and then passes it to the mouth of the other, usually through kissing.