Barebacking usually refers to a conscious and deliberate choice to forgo condoms. 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. As a form of non-penetrative sex, it can be done for its own enjoyment or as foreplay. Typically featured are hitting, choking, name-calling and hair-pulling. Among swinging couples, one of the two partners is often the driving force and the other is more passive-supportive of the addition of additional sex parties. The strategies and tactics that are used to smuggle one of the couple into and out of the toilet undetected are as important or almost as important as the urination. Pro-am pornography is sub-genre of amateur pornography that refers to professionally made porn that features amateur actors/actresses, often appearing for the first time in a pornographic film. Sometimes one or more fingers may be inserted into the vagina to stroke its frontal wall where the G-spot may be located. Femdom big tit milf features BDSM scenes in which the dominant partner is female. Biological anthropologist Helen B. The niche popularity grew videos gays significantly in the latter half of the first decade of the 2000s. Today, pornographic films can be sold or rented on DVD, shown through Internet and special channels and pay-per-view on cable and satellite, and in adult theaters. In the fetish cuckolding subculture, it is most common for the female to take on the sexually dominant role and the male the submissive role, however, female subs, sometimes referred to as cuckqueans, also exist. Internal ejaculation shots are a comparatively recent development in pornography; they are not found in early pornographic films. Lolita pornography features women who are 18 years old or slightly older, who pretend to be underage teen girls. Other fetish Bareback pornography features performers who are not wearing condoms. John Stagliano is considered to have started the 3d hentai gonzo pornography genre with his Buttman series of films.