Since at least 1973, it has also been used to refer to a sexually attractive young woman. Targets the male audience, but is much less popular than Yaoi. Participants usually derive pleasure from this, even though many of the practices—such as inflicting pain or humiliation or being restrained—would be unpleasant under other circumstances. Omorashi: The act of holding one own urine until the need to urinate is urgent, making another hold in their urine, or watching another person with an urgent need to urinate. Saliva pornography involves salivation and saliva. Actual spying may violate privacy and/or trespassing laws in many countries. Although interracial pornography theoretically can apply to depictions of sexual activity between performers of any different racial groups, the term is most commonly used for heterosexual sex acts between black and white performers. Men and women may masturbate until they are close to orgasm, stop for a while to reduce excitement, and then resume masturbating. A variation on this is to place the fingers and thumb on the penis as if playing a flute, and then shuttle them back and forth. The person sat upon may be in bondage, sexually submissive, or simply held down by the body-weight of the other person. Some restrict a policy of panties/nipple tape for females and some allow full nudity with explicit sexual interaction allowed. It may also involve touching, rubbing, or pinching the nipples or other erogenous zones while masturbating. This technique may include videos gays the use of a simulacrum, or mature milfs artificial vagina. The consent and compliance for a sadomasochistic situation can be granted only by people who can judge the potential results. English adopts and uses hentai as a genre of pornography by the commercial sale and marketing of explicit works under this label. In addition to mainstream pornography, the popularity of facials has led to creation of its own niche market, like video series that specialize in showing the act. It is commonly depicted in pornography, but very rarely in mainstream cinema.