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 . The Silent Duck, also called Duck-Billing, is the technique often used in which the person hentai videos engaging in hand insertion shapes the hand to resemble a duck beak. The first explicit pegging scene is believed to have been in the 1975 pornographic film The Opening of Misty Beethoven. Bukkake is a sex act portrayed in pornographic films, in which several men ejaculate on a woman, or another man. Sexual orientation Pornography features an increasing variety of combinations of actors by their sexual orientation such as lesbian, gay, bisexual, and transsexuals in addition to traditional heterosexual roles. Normal quantities of ejaculate range from 1.5 to 5.0 milliliters . This may help them develop their orgasm, increase its pleasure, and may inspire them to masturbate on a more frequent basis. Compensating elements of the total dominance and submission are care and devotion complementing one another, thus facilitating stable relationships. This makes varying degrees of stimulation an integral part of oral sex for many men. Fisher said that perhaps, the fleshy, rounded buttocks attracted males during rear-entry intercourse. A pornographic work is characterized as hardcore if it has any hardcore content, no matter how small. 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. Double Stuffed , Double Vaginal , or Double Anal pornography involves big tit milf the penetration of one orifice by two penises or other objects. When the interest in a particular subject is obsessive, gay bear porn the behavior may be described as stalking. Foot fetishism has been defined as a pronounced sexual interest in the feet or footwear.