Pornography is often distinguished from erotica, which consists of the portrayal of sexuality with high-art aspirations, focusing also on feelings and emotions, while pornography involves the depiction of acts in a sensational manner, with the entire focus on the physical act, so as to arouse quick intense reactions. Evolutionary psychologists suggest that rounded buttocks may have evolved to be desirable trait because they provide a visual indication hentai porn of the woman youth and fertility. New York photographer Irving Klaw also published illustrated adventure/bondage serials by fetish artists Eric Stanton, Gene Bilbrew, Adolfo Ruiz and others. Some aspects of the research community distinguish between female ejaculation and what is colloquially known as squirting or gushing. Buttocks are sometimes emphasized in pornography, where they are often referred to as booty. Bukkake naked milf is a sex act portrayed in pornographic films, in which several men ejaculate on a woman, or another man. It is typically animated pornography, as the legal age to be featured in a pornographic film in Japan is 18. Pornography gay bear porn may fall into more than one genre. In Japan, point of view pornography is referred to as hamedori . Preggo pornography features pregnant performers and may include erotic lactation as a fetish. Participants who exert sexual control over their partners are known as dominants or tops while participants who take the passive, receiving, or obedient role are known as submissives or bottoms. A related term used in the genre is the term cougar, which implies an older woman as predator. Macrophilia is a fascination with or a sexual fantasy involving giants, more commonly expressed as giantesses . Common positions include lying on back or face down, sitting, squatting, kneeling or standing. The act may be carried out face to face, or head to tail, with the woman recommended to be on top if she has smaller breasts. 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.