Each participant may engage in any type of sex acts with one or both of the others, such as vaginal, anal or oral sex or mutual masturbation. 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 term Asiaphile is sometimes used to describe the same phenomenon as is yellow fever . Some women who engage in same-sex sexual activity may reject not only identifying as lesbians but as bisexual as well, while other women self-identification as lesbian may not align with their sexual orientation or sexual behavior; sexual identity is not necessarily the same as one sexual orientation or sexual behavior, due to various reasons, such as the fear of identifying their sexual orientation in a homophobic setting. Adult animation is genre of animation geared towards adults and sometimes teens. Performers are usually clean-shaven, thinner and more effeminate than ones in mainstream gay pornography. Most soft crush fetishists avoid being placed under the same label as hard crush fetishists, believing that crush films with larger animals give the entire group a bad label. Bondage/BDSM Bondage pornography features performers tied up or constrained in various ways. Reality pornography is professionally made porn which seeks to emulate the style of amateur pornography. Mammary intercourse is said by Alex Comfort to produce mutual orgasm in women with sensitive breasts , and it was one of the nine substitute exercises for penetrative sexual activities, momporn as detailed in the Paradis Charnels of 1903. Entacle erotica describes a type of pornography most commonly found in Japan which integrates traditional pornography with elements of bestiality and a fantasy, horror, or science-fiction theme. Threesome anime hentai can also refer to a love triangle, a three-way romantic relationship. Is also common of the furry genre. Lesbian pornography made for women is usually made by women, and usually features women who identify gay movies as lesbian or bisexual.