Mammary intercourse is a sex act, performed as foreplay or as non-penetrative sex, that involves the stimulation of the male penis by the female breasts and vice versa. The term pearl necklace is used by some because the drops of semen deposited by the man resemble a necklace of translucent white pearls. Reality pornography is professionally made porn which seeks to emulate the style of amateur pornography. The reverse of this, in hot gay sex which nude women interact with clothed men, is called Clothed male, naked female . The Silent Duck, also called Duck-Billing, is the technique often used in which the person engaging in hand insertion shapes the hand to resemble a duck beak. Normal quantities of ejaculate range from 1.5 to 5.0 milliliters . It is also followed by dedicated industry publications and trade groups as well as the mainstream press, private organizations , government agencies, and political organizations. Other fetish Bareback pornography features performers who are not wearing condoms. Tentacle erotica can be consensual, but frequently contains elements of non-consensual sex. Transsexual pornography is a genre of pornography. Often, strong views are expressed with regard to anal sex; it is controversial in various cultures, especially with regard to religion, commonly due to prohibitions against anal sex among gay men or teachings about the procreative purpose of sexual activity. Some men also enjoy anal stimulation, with fingers or otherwise, without any prostate stimulation. Pornography may be presented in a variety of media, including books, magazines, postcards, photographs, sculpture, drawing, painting, animation, sound recording, film, video, and video games. Since the 1980s, many practitioners and organizations have adopted the motto safe, sane and momporn consensual, commonly abbreviated as SSC, which means that everything is based on safe activities, that all participants be of sufficiently sound/sane mind to consent, and that all participants do consent. This may help them develop their orgasm, increase its pleasure, and may inspire them to masturbate on a more frequent basis.