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 industry generally refers to such films as adult films, which is part of adult entertainment. Diaper fetishism, nappy fetishism or diaperism, is a sexual fetish in which a person feels a desire to wear or use diapers. 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. Additionally, the buttocks give an indication of the shape and size of the pelvis, naked milf which impacts reproductive capability. Group sex pornography features at least two men and two women , usually more, who all perform sex acts on each other. On May 27, 2010 the television gay twink porn program The Doctors discussed the topic with dozens of teens, parents, and professionals. Tentacle erotica can be consensual, but frequently contains elements of non-consensual sex. In some scenes or relationships it may be impossible for consent to be withdrawn in the middle of a scene, or the bottom may have the ability to revoke consent for a relationship as a whole, but not for a particular scene. Foot fetish pornography features heavy emphasis on the feet of the participants, either in combination with kissing and genital sex or in the context of acts such as trampling or crush fetishism. The term combines elements of the Freudian psychoanalytic fetish and the Marxist commodity fetish, and is used in the context of British, Spanish and French colonialism and imperialism and their aftereffects. Bondage/BDSM Bondage pornography features performers tied up or constrained in various ways. A homosexual threesome would involve either three men or three women. Bondage websites and bondage imagery hentai movies 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.