Mammary intercourse is said by Alex Comfort to produce mutual orgasm in women with sensitive breasts , and it was one of the nine substitute exercises for penetrative sexual activities, as detailed in the Paradis Charnels of 1903. In some areas, there are laws stating it is not legally possible to consent to be killed, and elsewhere it may still be legally dubious . As of 2010, they were reported to live together as a monogamous couple outside of their porn careers and want to continue working together for another 50 years. Foot fetishism, foot partialism, foot worship, or podophilia is a pronounced sexual interest in feet. For uncircumcised males, stimulation of the penis in this way comes from the pumping of the foreskin, in which the foreskin is held and slid up and down over the glans, which depending on foreskin length, is completely or partially covered and then uncovered in a rapid motion. It is mutual consent that makes a clear legal and ethical distinction between BDSM and such crimes as sexual assault or domestic violence. Saliva pornography involves salivation and saliva. Snuff pornography involves the actual death of any of the participants, consenting or otherwise, simulated death is not considered snuff. These scenes may either have the cameraman directly engaging in sex or merely filming others having sex. This style of filming is in contrast to having a hentai porn separate, third-person camera crew filming all the action. Internal ejaculations, followed by images of semen dripping from the anus, are sometimes depicted in bareback gay pornography, where they are referred to by the term breeding or the reverse money shot. Central big tit milf to the typical MILF narrative is an age-play dynamic of older women and younger lovers. There is also some evidence that pornography can be used to treat voyeurism. The term hentai is never used in this context in Japanese. Individuals who can change between top/dominant and bottom/submissive roles—whether from relationship to relationship or within a given relationship—are known gay sex video as switches, though the term switch in this context is occasionally seen as derogatory and is rejected by many who might simplistically fit the definition.