Pornography may be presented in a variety of media, including books, magazines, lesbian milfs postcards, photographs, sculpture, drawing, painting, animation, sound recording, film, video, young gay porn and video games. Dwarfs or midget pornography features performers who are dwarfs/midgets. Normal quantities of ejaculate range from 1.5 to 5.0 milliliters . 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. A variant of A2M is ATOM where a performer inserts his penis directly from one recipient anus into a second recipient mouth. Each participant may engage in any type of sex acts with one or both of the others, such as vaginal, anal or oral sex or mutual masturbation. A crush fetish is a fetish in which one is sexually aroused usually when someone crushes objects, food, and sometimes small animals with their body, usually under their foot, or when crushed oneself. It is used, for example, at fertility clinics to stimulate sperm donors. Actual upskirt or downblouse shots may violate privacy laws in some countries. Starting with erotic stories and woodblock prints from before the 20th century, Japanese pornography evolved into distinct subcategories with the media that in addition of pornographic videos and magazines featuring live actors, there is exist categories of pornographic manga , pornographic computer games , and pornographic anime . Mammary intercourse is said by Alex Comfort to produce mutual orgasm in women with sensitive breasts , and it was one of the nine substitute exercises for penetrative sexual activities, as detailed in the Paradis Charnels of 1903. Advocates of RACK argue that SSC gay hentai can hamper discussion of risk because no activity is truly safe, and that discussion of even low-risk possibilities is necessary for truly informed consent.