As women, they face concerns separate from men. HIV is among the infections that require such direct contact and is momsex therefore very unlikely to be transmitted via mammary intercourse. In the 18th and 19th centuries, some European theologians and physicians described it as heinous, deplorable, and hideous, but during the 20th century, these taboos generally declined. Yaoi is anime or manga that features gay males . The activity is done by itself 3d hentai or as a part of or prelude to other activities which many times involve sex. Preggo pornography features pregnant performers and may include erotic lactation as a fetish. Arcane or occult pornography involves sexualized situations with an occult or magical tone or performers who costume themselves in keeping with the theme, for example, a male performer dressed as a wizard. Such ejaculation can be done by mammary intercourse, or masturbation over the other person, or result from the withdrawal of the penis from a partner mouth as he is ejaculating following fellatio, irrumatio, or intercourse. Specific sex acts Anal Anal pornography features anal penetration with a penis, dildo, other objects, or some combination of them. While anal sex is commonly associated with male homosexuality, research shows that not all gay males engage in anal sex and that it is not uncommon in heterosexual relationships. Testosterone discourages fat storage in these areas. Bondage websites and bondage imagery in mainstream pornography As of 2003, specialist bondage magazines were mostly displaced by the availability of bondage material on the World Wide Web, and the presence of bondage imagery in mainstream pornographic magazines such as Nugget and Hustler Taboo magazine. Both sexes sometimes apply lubricating substances to intensify sensation. Studies have found that masturbation is frequent in humans of both sexes and all ages, although there is variation. Bukkake pornography involves a performer, usually female, onto whom several men or women ejaculate, usually on the gay cock face.