A variant of this is known as ATOM or ATOGM where the insertive partner removes his penis from one recipient anus and inserts it into a second recipient mouth. POV pornography involves camera angles designed to provide the viewer a view similar to that seen by one of the participants, whose face is never shown. In gay pornographic movies, actors who identify themselves as heterosexual, but who nevertheless perform explicit sexual acts with other males on film do not face the same stigmas as the mainstream acting counterparts and indeed can rise quickly to being featured actors. Amateur porn has been called one of the most profitable and long-lasting genres of pornography. Individuals who can change between top/dominant and bottom/submissive roles—whether from relationship to relationship or within a given relationship—are known as switches, though the term switch in this context is occasionally seen as derogatory and is rejected by many who might simplistically fit the definition. It can be combined with fellatio and the woman may move her breasts up and down on the penis for an additional stimulation, usually before the man reaches orgasm. Pornographic films are generally classified into sub-genres which describe the sexual fantasy which the film and actors attempt to create. Consent is the most important criterion here. For other scenes, particularly in established relationships, a safeword may be agreed to signify a warning rather than explicit withdrawal of consent; and a few choose not to use a safeword at all. Pornography is generally classified as either softcore or hardcore pornography. Unlike the traditional definition of the term, in fetish usage a cuckold is complicit in their partner sexual infidelity gay sex videos and takes masochistic sexual pleasure in it. They cited the Internet and text messaging as common ways of organising meetings. Fantasies of group sex are extremely common among both men and women, and group sex is a subgenre in pornographic films. With second wave feminism and growth of scholarship in women history and sexuality in the 20th century, the definition of lesbian broadened, sparking a debate about sexual desire as the major component to define what a lesbian is.