This can, however, videos gays redirect semen into the bladder . Stimulating the prostate from outside, via pressure on the perineum, can be pleasurable as well. 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. Once insertion is complete, the fingers are either clenched into a fist or kept naked milf straight. Detective magazines, comic books gay hentai and early fetish magazines In the early 20th century, Detective magazines covertly provided a way of publishing bondage imagery. If dramatic skills are not involved, a performer in a porn film may also be called a model. Solo performances in gay pornography have been described in 1985 as either or both active and/or passive , whereas female solo performances are said to be exclusively passive . The term applies to the depiction of the act rather than the act itself, and so does not include live exhibitions like sex shows and striptease. 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. Double penetration of the vagina, anus and mouth, can involve: Simultaneous penetration of the anus by two penises or other objects. When the interest in a particular subject is obsessive, the behavior may be described as stalking. The term pearl necklace is used by some because the drops of semen deposited by the man resemble a necklace of translucent white pearls. Group sex most commonly takes place in a private sex party or semi-public swinger gathering, but may also take place at massage parlors or brothels or, in some jurisdictions, at purpose-built locations such as sex clubs. The genres of pornography are based on the type of activity featured and the category of participants, for example mateur pornography is a category of pornography that features models, actors or non-professionals performing without pay, or actors for whom this material is their only paid modeling work.