Amateur porn has been called one of the most profitable and long-lasting genres of pornography. Foot fetishism, foot partialism, foot worship, or podophilia is a gaysex pronounced sexual interest in feet. This is commonly called double anal or double stuffing. Depictions of male and female masturbation are common in pornography, including gay naked milf pornography. The most common depiction of a hermaphrodite is a person with a female face, breasts, and build, and a penis , although there are other combinations. A female dominant in a master/slave relationship is often termed a Mistress, not to be confused with the colloquial usage of mistress as a kept sexual partner without a similarly formalized power relationship. Cum-shot pornography features a collection of male ejaculation scenes. The terms can be complimentary or pejorative. Sex experts have praised various techniques that the performer can use during fellatio to increase their partner pleasure. Tentacle rape or shokushu goukan is found in some horror or hentai titles, with tentacled creatures having sexual intercourse with female characters. Lucky Pierre is slang for a person performing both receptive and insertive anal and/or vaginal sex simultaneously during a threesome, being positioned between the two partners. The stimulation may involve hands, fingers, everyday objects, sex toys or combinations of these. Others involve partners who naturally have a significant difference in size. Masturbation has been depicted in art since prehistoric times and is mentioned and discussed in very early writings. Bareback sex is physical sexual activity, especially sexual penetration, without the use hentai videos of a condom. Some couples use pornography at times for variety and to create a sexual interest or as part of foreplay. It is also often mixed with other fetishes in practice, such as voyeurism, denial, etc. It may be used as foreplay, or as an alternative to sexual penetration. Unlike erotic films, pornographic films contain explicit sexuality and do not claim any artistic merit.