Following the introduction of the Motion Picture Association of America film rating system, independent animation producers attempted to establish an alternative to mainstream animation. The name was coined from the title of the controversial book. Bear features a combination of middle-aged, hairy or overweight males. Barebacking usually refers to a conscious and deliberate choice to forgo condoms. If one person is penetrated by two objects, it is generically called double penetration . A spanking may be carried out with the use of a bare or gloved hand, or with any of a variety of implements, including a paddle, strap, hairbrush, feather duster or belt. Particular areas and processes of the body that change during pregnancy may also become the focus of psychological investment, but nudity or sexual activity is not always essential, and in some cases actual pregnancy is not necessary to invoke arousal. Reading or viewing pornography, sexual fantasy or other erotic stimuli milf fuck may lead to a desire for sexual release such as by masturbation. Clothed male, naked female is one-sided female nudity in which one or more females are nude while one or more men are clothed. Reality and voyeur pornography, animated videos, and legally prohibited acts also influence the classification of pornography. 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 hentai porn between heterosexuals and homosexuals. HIV is among the infections that require such direct contact and is therefore very unlikely to be transmitted via mammary intercourse. 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. Examples of mentally oriented videos porno gay practices are education games, during which the dominant requires certain forms of behavior from the submissive.