Coprophilia , also called scatophilia or scat , is the paraphilia involving sexual arousal and pleasure from feces. However, gay pornography in the modern world is mostly concentrated in the making of home videos , cable broadcast and emerging video on demand and wireless markets, as well as images and movies for viewing on the Internet. Medical pornography involves sexualized medical, often fake, including gynecological pelvic examinations, rectal examinations, and pelvic or gynecological ultrasounds. Some masturbate only using pressure applied to the clitoris lesbian hentai without direct contact, for example by pressing the palm or ball of the hand against underwear or other clothing. The preference could be barefoot, big tit milf high-heels, flip flops, and so on, depending on the fetishist. As women, they face concerns separate from men. Group sex also occurs in populations of non-human animals such as bonobo apes and chimpanzees. Tentacle erotica features tentacled creatures raping or otherwise penetrating women or men. A study of 164 males in Finland from two SM clubs found that 18.2% had engaged in coprophilia; 3% as a sadist, 6.1% as a masochist, and 9.1% as both. 18% of heterosexuals and 17% of homosexuals in the study pool had tried coprophilia, showing no statistically significant difference between heterosexuals and homosexuals. Some prefer a particular type of clothing to urinate. In a few relationships, it leads as far as total submission of one partner in the truest sense of the phrase total videos porno gay power exchange . Some people masturbate by using machines that simulate intercourse. Reality pornography is a genre of pornography where staged scenes, usually shot in cinéma vérité fashion, set up and precede sexual encounters. In some creampie films, both gay and straight, intercourse and internal ejaculation are followed by performers licking up the semen that has dripped from their bodies. Particularly, some pornography in this genre features butch women, who are almost never seen in mainstream pornography.