Breast fetishism is a paraphilic sexual interest focused on female breasts . A scene where many women have sex with one man is referred to as a reverse gang-bang. The two sets of people involved often meet either randomly or arrange to meet up beforehand over the Internet. The allusion is to the use of hemp rope for restraining prisoners, as a symbol of power, in the same way that stocks or manacles are used in a Western BDSM context. A pornographic work is characterized as hardcore if it has any hardcore content. Jeffrey Masson has even argued that incest porn is the very nucleus of pornography — its prototypical form. In these research publications, it is suggested that real female ejaculation is the release of a very scanty, thick, and whitish fluid from the female prostate, while the squirting or gushing shown frequently in pornography is a different phenomenon, the expulsion of clear and abundant fluid, which has been shown to be a diluted fluid from the urinary bladder. Nubile refers to a young woman who is ready or suitable for marriage by virtue of her age or maturity. Some people masturbate by using machines that simulate intercourse. The queening stool hot gay sex 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. For a foot fetishist, points of attraction include the shape and size of the foot and toes , jewelry , treatments , state of dress , odor, and sensory interaction . Tentacle erotica features tentacled creatures raping or otherwise penetrating hentai sex women or men. Crush pornography features objects being crushed by an actress or actor, who generally plays an overtly dominant role. A spanking may be carried out with the use of a bare or gloved hand, or with any of a variety of implements, including a paddle, strap, hairbrush, feather duster or belt. Cheerleader pornography involves pictures of cheerleaders, both staged and real. The precise definition of roles and self-identification is a common subject of debate, reflection, and discussion within the community.