The most common male masturbation technique is simply to hold the penis with a loose fist and then to move the hand up and down the shaft. Typically featured are hitting, hentai sex choking, name-calling and hair-pulling. Double Stuffed , Double Vaginal , or Double Anal pornography involves the penetration of one orifice by two penises or other objects. There are number of types of sex parties: Swinger party/gathering A swinger party or partner-swapping party is a gathering at which individuals or couples in a committed relationship can engage in sexual activities with others as a recreational or social activity. Solo pornography recognized with AVN Awards include the All Alone series and All Natural: Glamour Solos. The most common type of erotic spanking is administered on the bare buttocks, but can also be combined with bondage, in order to heighten sexual arousal and feelings of helplessness. Is also common of the furry genre. Bukkake pornography involves a performer, usually female, onto whom several men or women ejaculate, usually on the face. It is geared towards heterosexual men, who most typically define a threesome as such. Commenting on why there are not as many female macrophiles, psychologist Helen Friedman theorized that because women in most societies already view men as dominant and gay bear porn powerful, there no need for them to fantasize about it. Its gain in prominence has been attributed to its depiction in the film Pecker, which was released in 1998. Real medical shots or videos may violate privacy laws in some countries. 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 momporn of the other, usually through kissing. Bondage websites and bondage imagery in mainstream pornography As of 2003, specialist bondage magazines were mostly displaced by the availability of bondage material on the World Wide Web, and the presence of bondage imagery in mainstream pornographic magazines such as Nugget and Hustler Taboo magazine.