There has been an increase in discussion and portrayal of masturbation in art, popular music, television, films, and literature. Examples hot gay sex of heterosexual pornographic film series featuring creampies include Cream Filled Teens and Internal Cumbustion. By Japanese law, the genitals of actors and actresses must be censored and up the mid-1990 so was the depiction of pubic hair. Sexologist Alfred Kind suggested that the buttocks is the primary sexual presentation site in primates. As of 2013, little analysis of this paraphilia has been reported in medical literature. The person receiving anilingus is regarded as the passive partner in the act, and the person performing anilingus is the active partner. It is used, for example, at fertility clinics to stimulate sperm donors. 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. Most soft crush fetishists avoid being placed under the same label as hard crush fetishists, believing that crush films with larger animals give the entire group a bad label. A male voyeur is commonly labeled Peeping Tom, a term which originates from the Lady Godiva legend. 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. Reality pornography is professionally made porn which seeks to emulate the style of amateur pornography. Transsexual porn star Wendy Williams has stated that transsexual Porn is classified as Straight Specialty. The term Asiaphile is sometimes used to describe the same phenomenon as is yellow fever . As a result, little in history was documented to give an accurate description of how female homosexuality is expressed. A sub-set of vaginal fisting attempts to photograph the female cervix immediately big tit milf after the fist is removed from the now-gaping hentai porn vagina.