The term is typically used by the cinematographer within the narrative framework of a pornographic hentai porn film, and since gay sex video the 1970s has become a leitmotif of the hardcore nude milfs genre. Mammary intercourse is known as titty-fucking, titfuck, or a titjob in the United States, as well as tit wank or French fuck in the United Kingdom - the latter term dating back to the 1930s; while a more jocular equivalent is a trip down mammary lane. Sub-genres can also be classified into the characteristics of the performers or the type of sexual activity on which it concentrates, and not necessarily on the market to which each sub-genre appeals. Interactive pornography, available in CD-ROM and DVD format, allows the viewer to select the particular acts performed at any one time, sometimes with the camera providing a first person view. Participants who exert sexual control over their partners are known as dominants or tops while participants who take the passive, receiving, or obedient role are known as submissives or bottoms. Throughout history, women have not had the same freedom or independence to pursue homosexual relationships as men, but neither have they met the same harsh punishment as homosexual men in some societies. When used as an alternative to penile-vaginal penetration, the goal may be to preserve virginity or to prevent pregnancy. A survey by the New York City Department of Health and Mental Hygiene found that heterosexual women are more likely to bareback when engaging in anal sex than homosexual and bisexual men. Female dominance refers to BDSM relationships and BDSM scenes in which the dominant partner is female. Pornographic films are typically categorized as either softcore or hardcore pornography. These actors often play the top roles but this is not always the case, such as with Kristen Bjorn and some Bel Ami models. Such ejaculation can be done by mammary intercourse, or masturbation over the other person, or result from the withdrawal of the penis from a partner mouth as he is ejaculating following fellatio, irrumatio, or intercourse.
