Ass to mouth pornography shows the transfer of a performer penis from a second performer anus to that same second performer mouth in a single shot. The padding may also muffle noises from the outside, causing a relaxation effect and heightening their other senses. 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. The original definition of dogging – and which is still a closely related activity – is spying on couples having sex in a car or other public place. A celebrity may allow such a recording to surface willingly, as part of a publicity stunt. A common way that these hentai videos are depicted in a single scene is milf xxx with one woman and two men performing gaysex together. In addition to mainstream pornography, the popularity of facials has led to creation of its own niche market, like video series that specialize in showing the act. Going back at least as far as the Christy twins in the 1970s, depictions of incest and particularly incest between twins has been a feature of gay pornography. Bottom and submissive are widely recognized terms for those partner in the relationship or activity who are, respectively, the physically receptive or controlled participants. A crush fetish is a fetish in which one is sexually aroused usually when someone crushes objects, food, and sometimes small animals with their body, usually under their foot, or when crushed oneself. The term discipline describes psychological restraining, with the use of rules and punishment to control overt behavior. Even though the performers who perform in these films typically appear on many reality websites within a short span of time, most of these websites claim that each of them is an amateur. Male masturbation may differ between males who have been circumcised and those who have not. The work of Bruce Seven has been called reality porn, due to his lack of using scripts and asking his performers to act naturally in their own character.