The range of its individual characteristics is thereby wide. It contains graphic sexual activity and visible penetration. For legal reasons, the vast majority of so-called reality milf xxx porn involves professional naked celebrities actors and actresses posing as so-called amateurs. Diaper fetishism is totally independent from pedophilia as the wearer derives pleasure only from the diaper and/or use of it. Both sexes sometimes apply lubricating substances to intensify sensation. This fetish sometimes originates from childhood memories of needing, or of seeing another needing, to urinate. Several hundred exclusively pegging films were produced, as well as twice as many bisexual and straight films with strap-on scenes. It is commonly depicted in pornography, hentai sex but very rarely in mainstream cinema. The reverse of this, in which nude women interact with clothed men, is called Clothed male, naked female . There is, however, no third party camera work involved. This can, however, redirect semen into the bladder . In modern BDSM vernacular, the queening stool allows open access to the crotch while seated. This industry employs thousands of performers along with support and production staff. As of 2013, little analysis of this paraphilia has been reported in medical literature. It is sometimes combined with BDSM features. The person receiving anilingus is regarded as the passive partner in the act, and the person performing anilingus is the active partner. In S/M, the Sadist is usually the Top and the Masochist the Bottom, but these roles are frequently more complicated or jumbled . John Stagliano is considered to have started the gonzo pornography genre with his Buttman series of films. Celebrity sex celeb sex tapes tapes are videos porno gay amateur or professionally-made recordings of sex gay cocks acts, as performed by a celebrity and their partner. Heterosexual bareback sex, as opposed to sex with condoms, not only poses an increased risk of STIs, but for pregnancy as well. 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.