Bisexual pornography is a genre of pornography which most typically naked milf depicts one woman and two men who all perform sex acts on each other. Mammary intercourse is said by Alex Comfort to produce mutual orgasm in women with sensitive breasts , and it was one of the nine substitute exercises for penetrative sexual activities, as detailed in the Paradis Charnels of 1903. A celebrity may allow such a recording to surface willingly, as part of a publicity stunt. Along with the penis, the scrotum is sensitive and considered to be an erogenous zone. Another variant of reality pornography consists of normal couples that are filmed by professionals, in which case the only obvious distinction from amateur pornography is the higher quality of production, filming and editing. Teacher and Student or Boss and Secretary pornography involves sexualized situations which take place between an authority figure, such as a teacher or boss, and an underling, such as a student or secretary, often fake. Fisting involves the insertion of one partner entire hand into a vagina or the anal cavity. Hugo Ohira, director of marketing for Silvercash, rhetorically asks Who does not like spewing their load on a pretty young face? Mutual masturbation is a sexual act where two or more people stimulate themselves or one another sexually, gay hentai usually with the hands. Unlike erotic films, pornographic films contain explicit sexuality and do not claim any artistic merit. Interracial pornographic films have experienced an explosion in popularity, becoming one of the fastest-growing and biggest-selling genres. In pornography, depictions of lesbian sex form a popular hot gay sex subgenre, directed toward a male heterosexual and female homosexual audience. Participants usually derive pleasure from this, even though many of the practices—such as inflicting pain or humiliation or being restrained—would be unpleasant under other circumstances. Group sex is sexual behavior involving more than two participants. The rise of the Internet in the late 1990s and early 2000s similarly changed the way pornography film was distributed and furthermore complicated the censorship regimes around the world and the legal prosecution of obscenity.