Last updateMon, 01 Sep Some people masturbate by using machines that simulate intercourse. Typically features adult, masculine men with varying degrees of muscle, body fat, and body hair, akin to beefcakes, or bears. The cover can have hinges or be a separate part. Voyeur pornography may also include shots of topless women on topless beaches who are unaware of the cameras but may legally be photographed due to the public setting. If one person is penetrated by two objects, it is generically called double penetration . Crush pornography features objects being crushed by an actress or actor, who generally plays an overtly dominant role. Lolita pornography features women who are 18 years old or slightly older, who pretend to be underage teen girls. Arcane or occult pornography involves sexualized situations with an occult or magical tone or performers who costume themselves in keeping with the theme, for example, a male performer dressed as a wizard. Biological anthropologist Helen B. Coprophilia , also called scatophilia or scat , is the paraphilia involving sexual arousal and pleasure from feces. In 1988, a sex tape caused significant damage to Rob Lowe career. Among swinging couples, one of the two partners is often the driving force and the other is more passive-supportive of the addition of additional sex parties. A person may be sexually penetrated multiple times simultaneously. The queening stool is also related to a smotherbox, which also allows the person under the seat to be locked in place, restrained by the neck as in a set of stocks. Double penetration of the vagina, anus and mouth, can involve: Simultaneous penetration of the anus by two penises or other objects. In Japanese, the term describes any type of perverse or bizarre sexual desire or act; it does not represent a genre of work. For a foot fetishist, points of attraction include the shape and celebrity sextapes free size of the foot and toes , jewelry , treatments , state of dress , odor, and sensory interaction . It is geared towards heterosexual men, who most typically define a threesome as such.