It is mutual consent that makes a clear legal and ethical distinction between BDSM and such crimes as sexual assault or domestic violence. Going back at least as far as the Christy twins in the 1970s, depictions of incest and particularly incest between twins has been a feature of gay pornography. Pornography in the early 2000s. Unlike erotic films, pornographic films contain explicit sexuality and do not claim any artistic merit. Gloryhole pornography features women performing fellatio on unidentified men through a small hole made in a bathroom divider. Greater economic and social freedom allowed them gradually to be able to determine how they could form relationships and families. The term hentai is never used in this context in Japanese. The related term twinkle-toes, which implies that a man is effeminate, tends to be used in a derogatory manner. Bukkake, Gokkun, Omorashi, and mature milfs tentacle erotica are few uniquely Japanese genres known to western viewers. Sometimes special furniture is used, such as a queening stool or smotherbox. Reflective of its views on sexuality and culture, Japanese pornography delves into a wide spectrum of heterosexual, homosexual, and transgender sexual acts in addition to unique fetishes and philias. Now facial cumshots are regularly portrayed in pornographic films, gay hentai videos, magazines and internet web sites. As of 2010, they were reported to live together as a monogamous couple outside of their porn careers and want to continue working together for another 50 years. In some gay fuck societies, the terms fox, plum, chick, or chicken are preferred. Enema pornography involves adults given enemas to others, often fake. Bhabha, Anne McClintock and Kobena Mercer. To tea bag is a slang term for the sexual act of a man placing his scrotum in the mouth of a willing sexual partner for pleasure or onto the face or head of another person. Tentacle rape or shokushu goukan is found in some horror or hentai titles, with tentacled creatures having sexual intercourse with female characters.