Strictly speaking, bondage means binding the partner by tying their appendages together; for example, by the use of handcuffs or by lashing their arms to an object. Body parts including fingers, tongue and penis may be used for anonymous oral, vaginal and/or anal intercourse. Exhibitionist pornography features performers, usually female exposing themselves in public and spans simple flashing to public sex. Consent is the most important criterion here. However, the tradition of bondage magazines continues in the form of art books of bondage photographs, published by mainstream publishers such as Taschen. Emetophilia pornography gay hentai involving vomiting and gagging. Squirt pornography involves women ejaculating. Babysitter pornography features usually teenage girls being porn milf exploited and having taboo sex with older, male employers. Male masturbation may differ between males who have been circumcised and those who have not. In these cases, the appearance of an enlarged abdomen caused by obesity or overeating may be sufficient, or simply the suggestion of a protruding navel. 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. The most common depiction of a hermaphrodite is a person with a female face, breasts, and build, and a penis , although there are other combinations. Softcore pornography generally contains nudity or partial nudity in sexually suggestive situations, but without explicit sexual activity, sexual penetration or extreme fetishism, while hardcore pornography may contain graphic sexual activity and visible penetration, including unsimulated sex scenes. The anus has a relatively high concentration of nerve endings and can be an erogenous zone, and the receiver may receive pleasure from external anal stimulation. Fisting pornography features the insertion of an entire hand into a performer gay cock vagina or anus. The first pegging scene appears to have been in the non-pornographic 1970 film Myra Breckinridge, based on the novel of the same name by Gore Vidal, although it was not explicit.