The industry generally refers to such films as adult films, which is part of adult entertainment. Solo performances in gay pornography have been described in 1985 as either or both active and/or passive , whereas female solo performances are said to be exclusively passive . The resulting consent and understanding is occasionally summarized in a written contract, which is an agreement of what can and cannot take place. Following the introduction of the Motion Picture Association of America film rating system, independent animation producers attempted to establish an alternative to mainstream animation. Hentai narrow Japanese usage and broad international usage are often incompatible. Felching is a sexual gay movies practice involving the act of orally sucking nude milfs semen out of the vagina or anus of one partner. Creampie pornography features ejaculation inside the vagina , mouth or rectum instead of the common cum shot, followed by the visible seeping or dripping of semen from the vagina, mouth or anus. The Girls Gone Wild series is one example. The use of the word creampie to describe 3d hentai such scenes originated in U. There are number of types of sex parties: Swinger party/gathering A swinger party or partner-swapping party is a gathering at which individuals or couples in a committed relationship can engage in sexual activities with others as a recreational or social activity. Particular areas and processes of the body that change during pregnancy may also become the focus of psychological investment, but nudity or sexual activity is not always essential, and in some cases actual pregnancy is not necessary to invoke arousal. Behind the Green Door was one of the first pornographic films to feature sex between a white actress with a black actor . Real school shots or videos which are sexualized may violate privacy laws in some countries. Cartoon pornography depicts illustrated or animated fictional characters in erotic and sexual situations. Typically features adult, masculine men with varying degrees of muscle, body fat, and body hair, akin to beefcakes, or bears.