Snowballing or snowdropping is the human sexual practice in which one person takes someone else semen into his or her mouth and then passes it to the mouth of the other, usually through kissing. Sometimes one or more fingers may be inserted into the vagina to stroke its frontal wall where the G-spot may be located. Transsexual porn star Wendy Williams has stated that transsexual Porn is classified as Straight Specialty. John Stagliano is considered to have started the gonzo pornography genre with his Buttman series of films. However, various gay hentai groups within society considered such depictions immoral, labelling them pornographic, and attempting to have them suppressed under obscenity laws, with varying degrees of success. Starting with erotic stories and woodblock prints from before the 20th century, Japanese pornography evolved into distinct subcategories with the media that in addition of pornographic videos and magazines featuring live actors, there is exist categories of pornographic manga , pornographic computer games , and pornographic anime . Bondage/BDSM Bondage pornography features performers tied up or constrained in various ways. There are number of types of sex parties: Swinger party/gathering A swinger party or partner-swapping party is a gathering at which individuals or couples in a committed relationship can engage in sexual activities with others as a recreational or social activity. The niche popularity grew significantly in the latter half of the first decade of gay fuck the 2000s. This makes varying degrees of stimulation an integral part of oral sex for many men. Some may keep their hand stationary while pumping porn milf into it with pelvic thrusts in order to simulate the motions of sexual intercourse. Diaper fetishism is totally independent from pedophilia as the wearer derives pleasure only from the diaper and/or use of it. 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.