This genre also features male-on-male fellatio through a small 3d hentai hole made in a bathroom divider. Lolita pornography caters to ephebophiles. Clothed female, naked male pornography features naked men and clothed women; typically, the women humiliate and abuse the men or perform fellatio and/or handjobs on the men. Group sex also occurs in populations of non-human animals such as bonobo milf xxx apes and chimpanzees. The activity is done by itself or as a part of or prelude to other activities which many times involve sex. Creampie, also known as internal cum shot, and, in homosexual contexts, also known as breeding and seeding, is a slang term used in pornography to describe when a male ejaculates inside his partner vagina or anus. Patricia Hill Collins, an African-American gay bear porn writer, theorizes that this is derived from a stereotype that those of black descent are promiscuous, and their buttocks are objectified by porn as a result. Breast fetishism is a paraphilic sexual interest focused on female breasts . Gay pornography is the representation of sexual activity between males. Yaoi is anime or manga that features gay males . While some fantasize about a giantess who is slightly taller than himself, others are interested in giantesses that are hundreds or even thousands of feet tall. Female masturbation involves the stroking or rubbing of a woman vulva, especially her clitoris, with an index or middle fingers, or both. Bear features a combination of middle-aged, hairy or overweight males. Pegging films include Strap It On , Babes Balling Boys , Strap Attack, Strap-on Sirenz, Strap-on Chicks, Boss Bitches , various movies produced by LEDA Studios, and San Francisco-based Men In Pain. 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. It is geared towards heterosexual men, who most typically define a threesome as such. In the Diagnostic and Statistical Manual of Mental Disorders , published by the American Psychiatric Association, it is classified under 302.89 – Paraphilia NOS and has no diagnostic criteria other than a general statement about paraphilias that says the diagnosis is made if the behavior, sexual urges, or fantasies cause clinically significant distress or impairment in social, occupational, or other important areas of functioning.