In Japan, point of view pornography is referred to as hamedori . It contains graphic sexual activity and visible penetration. 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. Patricia Hill Collins, an African-American writer, theorizes that this is derived from a stereotype that those of black descent are promiscuous, and their buttocks are objectified by porn as a result. The most common male masturbation technique is simply to hold the penis with a loose fist and then to move the hand up and down the shaft. Such ejaculation can be done by mammary intercourse, or masturbation porn milf 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. Diaper fetishism is totally independent from pedophilia as the wearer derives pleasure only from the diaper and/or use of it. They may be noted for using risqué themes, graphic violence, sexuality or black comedy in a manner that is unsuitable for younger audiences. Specific sex acts Anal Anal pornography features anal penetration with a penis, dildo, other objects, or some combination of them. Portrayals of lesbians in the media suggest that society at large has been simultaneously intrigued and threatened by women who challenge feminine gender roles, and fascinated and appalled with women who are romantically involved with other women. Double penetration of the vagina, anus and mouth, can involve: Simultaneous penetration of the anus by two penises or other objects. Tentacle erotica can be consensual, hentai sex but frequently contains elements of non-consensual sex. Breast gaysex fetishism is a paraphilic sexual interest focused on female breasts . Masturbation is the self-sexual stimulation of the genitals for sexual arousal or other sexual pleasure, usually to the point of orgasm. The naked appearance of actress Demi Moore in the advanced stage of pregnancy on the cover of Vanity Fair magazine in 1991 marked the beginning of a period which has since seen pregnancy presented by celebrities as a glamorous state of living, while also creating a market for photographers to produce images of pregnant mothers, and for fashion stylists to introduce pregnancy styling to their business.