Today, pornographic films can be sold or rented on DVD, shown through Internet and special channels and pay-per-view on cable and satellite, and in adult theaters. Being forced to wear diapers as a form of humiliation is sometimes a behavior encountered in sexual masochism. See also Gay-for-pay. Diaper fetishism, nappy fetishism or diaperism, is a sexual fetish in which a person feels a desire to wear or use hentai sex diapers. During anal sex, male pleasure can be particularly derived from the prostate, which can lead to an orgasm and ejaculation. In humans, females generally have more round and voluptuous buttocks, caused by estrogen that encourages the body to store fat in the buttocks, hips, and thighs. A person may be sexually penetrated multiple times simultaneously. It is also followed by dedicated industry publications and trade groups as well as the mainstream press, private organizations , government agencies, and political organizations. Works in this genre may explore philosophical, naked milf political or social issues. The term is typically used by the cinematographer within the narrative framework gay bear porn of a pornographic film, and since the 1970s has become a leitmotif of the hardcore genre. 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. Lying face down one may use the hands, one may straddle a pillow, the corner or edge of the bed, a partner leg or some scrunched-up clothing and hump the vulva and clitoris against it. Erotic spankings are commonly combined with other forms of sexual foreplay. Ass to mouth is a slang term primarily used to describe the withdrawal of a penis from the receptive partner anus followed by the immediate insertion into the receptive partner mouth. In these research publications, it is suggested that real female ejaculation is the release of a very scanty, thick, and whitish fluid from the female prostate, while the squirting or gushing shown frequently in pornography is a different phenomenon, the expulsion of clear and abundant fluid, which has been shown to be a diluted fluid from the urinary bladder.