Low et al. Reality and voyeur pornography, animated videos, and legally prohibited acts also influence the classification of pornography. The consensual submission of the submissive is sometimes demonstrated to others by symbols indicating his/her belonging to the dominant, such as wearing a collar, special tattoos, piercings, a very short haircut or a bald head. Biological hentai sex anthropologist Helen B. Before the enforcement of the Hays Code, some cartoon shorts contained humor that was aimed at adult audience members rather than children. A woman can use a secondary vibrator, between the dildo and her genitals, to get pleasure from pegging. Bra pornography involves women or men dressed in bras. A person may be sexually penetrated multiple times simultaneously. Some may pursue fantasies that are concerned with the circumstances in which a subject may give birth, or to the conditions to which the pregnant subject may find themselves acting upon, such as approaches to mobility, sleeping, and dressing. Many times a top actor will then gaysex be sought as a bottom and the debut is often treated as a notable event or even its own release. While wearing diapers, a diaper fetishist generally experiences a comforting feeling. Reality pornography is a genre of pornography mature milfs where staged scenes, usually shot in cinéma vérité fashion, set up and precede sexual encounters. Real school shots or videos which are sexualized may violate privacy laws in some countries. As women, they face concerns separate from men. In a few relationships, it leads as far as total submission of one partner in the truest sense of the phrase total power exchange . Being forced to wear diapers as a form of humiliation is sometimes a behavior encountered in sexual masochism. Some people masturbate by using machines that simulate intercourse. Such works have also often been subject to censorship and other legal restraints to publication, display or possession. Such grounds and even the definition of pornography have differed in various historical, cultural, and national contexts.