Pornography may be presented in a variety of media, including books, magazines, postcards, photographs, sculpture, drawing, painting, animation, sound recording, film, video, and video games. The volume of semen that is ejaculated depends on several factors, including the male health, age, degree of sexual excitement, and the time since his last ejaculation. Lolita pornography features women who are 18 years old or slightly older, who pretend to be underage teen girls. Common positions include lying on back or face down, sitting, squatting, kneeling or standing. Other objects such as ball point pens and thermometers are sometimes used, although this practice can lead to injury and/or infection. Women oriented pornography is sometimes referred to as sex positive pornography. Some men also enjoy anal stimulation, with fingers or otherwise, without any prostate mature milfs stimulation. Female ejaculation is the expulsion of fluid by the paraurethral ducts through and around the human female urethra during or before an orgasm. Solo pornography recognized with AVN Awards include the All Alone series and All Natural: Glamour Solos. Interactive pornography, available lesbian hentai in CD-ROM and DVD format, allows the viewer to select the particular acts performed at any one time, sometimes with the camera providing a first person view. 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 . Pro-am pornography is sub-genre of amateur pornography that refers to professionally made porn that features amateur actors/actresses, often appearing for the first time in a pornographic film. Stimulating the prostate from outside, gay twink porn via pressure on the perineum, can be pleasurable as well. Irrespective of the legal or social view of pornography, it has been used in a number of contexts.