Many transgender people regard the term shemale as offensive, arguing that it mocks or shows a lack of respect towards the gender identity and gender expression of transgender individuals; in this view, the term emphasizes the biological sex of a person and neglects their gender. The most common male masturbation technique is simply to hold the penis with a loose fist and then to move the hand up and down the shaft. Once insertion is complete, the hentai sex fingers are either clenched into a fist or kept straight. Reality and voyeur pornography, animated videos, and legally prohibited acts also influence the classification of pornography. Additionally, the buttocks momsex give an indication of the shape and size of the pelvis, which impacts reproductive capability. The term is typically used by the cinematographer within the narrative framework of a pornographic film, and since the 1970s has become a leitmotif of the hardcore genre. 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. Bondage pornography specializes in the depiction of sexual bondage or BDSM activities as photographs, stories, movies, or drawings. A homosexual threesome would involve either three men or three women. It has also been recommended as a form of foreplay or safer sex. 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. Diaper pornography involves performers wearing diapers, sometimes with an adult performer acting in the role of a caretaker. In the gay pornography industry, which uses amateurs as well as professional actors, the term gay-for-pay refers to actors labeled or believed to be straight but who engage in same-sex sexual activities for money. Examples of mentally oriented practices are education games, during which the dominant requires certain forms of behavior from the submissive. The industry generally refers to such gay movies films as adult films, which is part of adult entertainment.