Transsexual pornography features transwomen performers, who typically have male genitalia and augmented female breasts . It may be regarded as taboo or unnatural, and is a criminal offense in some countries, punishable by corporal or capital punishment; by contrast, people also regard anal sex as a natural and valid form of sexual activity that may be as equally fulfilling as any other desired sexual expression. Though the term anal lesbian milfs sex most commonly means penile-anal penetration, sources sometimes 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. Various groups within society have considered depictions of a sexual nature immoral, labeling them pornographic, and attempting to have them suppressed under obscenity and other laws, with varying degrees of success. First found in softcore movies and erotic gay sex video thrillers, depictions of lesbianism entered mainstream cinema in the 1980s. Making a pearl necklace is one of the activities that sex workers use as safe sex alternatives for people who refuse to wear condoms. Some couples use a threesome as a way to develop a love triangle . Technically this is a form of exhibitionism rather than group sex per se. Watersports pornography features sexual activities involving urine, such as golden showers. Babysitter pornography features usually teenage girls being exploited and having taboo sex with older, male employers. Although pornography has usually focused on heterosexuality, due to the prevalence of the heterosexual orientation, explicit gay material has a long history as well, which reaches back to Greek antiquity, if not to prehistory. It can be combined with fellatio and the hentai movies woman may move her breasts up and down on the penis for an additional stimulation, usually before the man reaches orgasm. Actors are mostly amateur; any well-known actors in bisexual porn tend to be from the gay pornography industry.