There were also a very limited number of specialist fetish magazines which featured images of bondage, such as the famous Bizarre magazine published from 1946 to 1959 by the pioneering fetish photographer John Willie, and ENEG Exotique magazine, published 1956-1959. The sub-genres usually conform to certain conventions, and each may appeal to a particular audience. Well-known female porn stars who expressed their pleasure in pegging their male partners include Taylor Wane, Debi Diamond, Brittany Andrews, and Monique Covét. Amateur porn has been called one of the most profitable and long-lasting genres of pornography. When sexual activity is centered on one of naked milf the threesome, then the activity may be described as a gang bang of the person. Insertion in pornography features women inserting various odd objects into their anus or vaginas. Group sex can occur between people of all sexual orientations and genders. 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. By Japanese law, the genitals of actors and actresses must be censored and up the mid-1990 so was the depiction of pubic hair. Watersports pornography features sexual activities involving urine, such as golden showers. It may also involve touching, rubbing, or pinching the nipples or other erogenous zones while masturbating. Other possibilities are possible, such as a man having sex with two women who are having sex with each other. Fantasies of group sex are extremely common among both men and women, and group sex is a subgenre in pornographic films. It is sometimes described as a sexual fantasy, by women or men, depicting an exhibitionist or physique worship scenario. This fetish sometimes originates from childhood memories of needing, or of seeing another needing, to urinate. For uncircumcised males, stimulation of the lesbian hentai penis in this way comes from the pumping of the foreskin, gay movies in which the foreskin is held and slid up and down over the glans, which depending on foreskin length, is completely or partially covered and then uncovered in a rapid motion.