Common phrases used to refer to these individuals are chicks with dicks or the derogatory term shemale, although these are generally considered pejorative among transwomen. Medical pornography involves hentai movies sexualized medical, often fake, including gynecological pelvic examinations, rectal examinations, and pelvic or gynecological ultrasounds. It has since become popular enough with couples gay bear porn to be discussed during an episode of Sex and the City. Perhaps following the example set by gay pornography, they have become a popular subgenre within heterosexual pornography since the turn of the century, featuring both vaginal and anal ejaculations. A person may be sexually penetrated multiple times simultaneously. A woman can use a secondary vibrator, between the dildo and her genitals, to get pleasure from pegging. The industry generally refers to such films as adult films, which is part of adult entertainment. The term pearl necklace is used by some because the drops of semen deposited nude milfs by the man resemble a necklace of translucent white pearls. However, various groups within society considered such depictions immoral, labelling them pornographic, and attempting to have them suppressed under obscenity laws, with varying degrees of success. Although there may be no connection between coprophilia and sadomasochism , the limited data on the former comes from studies of the latter. His most famous model was Bettie Page, who became the first celebrity of bondage film and photography. A related term used in the genre is the term cougar, which implies an older woman as predator. Diaper fetishism is totally independent from pedophilia as the wearer derives pleasure only from the diaper and/or use of it. Reality and voyeur pornography, animated videos, and legally prohibited acts also influence the classification of pornography. There are various subcultures under this umbrella term and distinct difference between these subcultures. 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.