A related term used in the genre is the term cougar, which implies an older woman as predator. This genre also features male-on-male fellatio through a small hole made in a bathroom divider. 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. Masturbation is the self-sexual stimulation of the genitals for sexual arousal or other sexual pleasure, usually to the point of orgasm. They may regard it as an enhancing element of their sex lives or as their primary form of sexual activity. Studies have found that masturbation is frequent in humans of both sexes and all ages, although there is variation. Diaper fetishism, nappy fetishism or diaperism, is a sexual fetish in which videos gay a person feels a desire to wear or use diapers. The actual height of the giantess within the fantasy may vary depending on the individual. In the gay pornography industry, which uses amateurs as well as professional actors, the term gay-for-pay refers to actors labeled or believed to be straight but who engage in same-sex sexual activities for money. Behind the Green Door was one of the first pornographic films to feature sex between a white actress with a black actor . Specific sex acts Anal Anal pornography features anal penetration with a penis, dildo, other objects, or some combination of them. It contains graphic sexual activity and visible penetration. At the end of the evening the female partners would randomly select keys from the bowl and leave with that key owner. The loose and direct camera work often includes tight shots of the genitalia, unlike some traditional porn. To avoid soreness from this resulting friction, some may prefer to use a personal lubricant, masturbation cream or saliva during masturbation. Lolita pornography caters to ephebophiles. It is typically animated pornography, as the legal age to be featured in a pornographic film in Japan is 18.