The principal characteristic of voyeurism is that the voyeur does not normally interact directly with the subject of his/her interest, who is often unaware of being observed. Others may also use vibrators and other sexual devices more commonly associated with female masturbation. In the 1970s, the hardcore pornography genre introduced the stereotypical cumshot scene as a central element of the hardcore film, in which the male actor ejaculates in a way ensuring maximum visibility of the act itself. A large part of the popularity of these videos is seeing how regular and normal the girls are in real-life. Hugo Ohira, director of marketing for Silvercash, milf fuck rhetorically asks Who does not like spewing their load on a pretty young face? Though the term anal sex most commonly means penile-anal penetration, sources sometimes hentai sex use the term anal intercourse to refer exclusively to penile-anal penetration, and anal sex to refer to any form of anal sexual activity, especially between pairings as opposed to anal masturbation. One or more of the participants may engage in autoerotic sexual activity, such as masturbation, possibly without physical contact with the other participants. POV pornography involves camera angles designed to provide the viewer a view similar to that seen by one of the participants, whose face is never shown. First found in softcore movies and erotic thrillers, depictions of lesbianism entered mainstream cinema in the 1980s. Interracial pornography typically employs ethnic and racial stereotypes in its depiction of performers and many of interracial pornographic films still include racial stereotypes, although the segregation of actors by race has diminished considerably. Buck Angel is the best-known actor in this genre. Foot fetishism, foot partialism, foot worship, or podophilia is a pronounced sexual interest in feet. In gay pornographic movies, actors who identify themselves as heterosexual, but who nevertheless perform explicit sexual acts with other males on film do not face the same stigmas as the mainstream acting counterparts and videos gays indeed can rise quickly to being featured actors.