A homosexual threesome would involve either three men or three women. For example, in Australia it is rated Refused Classification . Some aspects of the research community distinguish between female ejaculation and what is colloquially known as squirting or gushing. Reality and voyeur pornography, animated videos, and legally prohibited acts anime hentai also influence gay bear porn the classification of pornography. Some may keep their hand stationary while pumping into it with pelvic thrusts in order to simulate the motions of sexual intercourse. BDSM communities generally welcome anyone with a non-normative streak who identifies with the community; this may include cross-dressers, extreme body mod enthusiasts, animal players, latex or rubber aficionados, and others. Hardcore pornography is pornography that depicts penetration or extreme fetish acts, or both. The range of its individual characteristics is thereby wide. Is also common of the furry genre. Works in this genre may be considered adult for any number of reasons. John Stagliano is considered to have started the gonzo pornography genre with his Buttman series of films. Bondage websites and bondage imagery in mainstream pornography As of 2003, specialist bondage magazines were mostly displaced by the availability of bondage material on the milf fuck World Wide Web, and the presence of bondage imagery in mainstream pornographic magazines such as Nugget and Hustler Taboo magazine. Group sex pornography features at least two men and two women , porn cartoon usually more, who all perform sex acts on each other. The full-weight body-pressure, moisture, sex odors and darkness can be perceived as powerful sexual attractions or compulsions. Types of anal sex can also be a part of lesbian sexual practices. Double Stuffed , Double Vaginal , or Double Anal pornography involves the penetration of one orifice by two penises or other objects. Lying face down on a comfortable surface such as a mattress or pillow, the penis can be rubbed against it. Transsexual pornography is a genre of pornography.