Men may find stimulation of the anus, rectum, and adjacent organs enjoyable. Urolagnia is a form of salirophilia in which sexual excitement is associated with the sight or thought of urine or urination. There may be more than two participants; both group sex and gang banging can be included. It is typically animated pornography, as the legal age to be featured in a pornographic film in Japan is 18. Sadomasochism is practiced in isolation relatively rarely, though some masochists report biting, pinching, or even stun-gunning themselves as a prelude to, or as part of, masturbation. The phrase is commonly found on porn sites. Bisexual pornography is a genre of pornography which most typically depicts one woman and two men who all perform sex acts on each other. Examples include the Girls Gone Wild and Girls Who Like Girls Series. A variant of A2M is ATOM where a performer inserts his penis directly from one recipient anus into a second recipient mouth. Bottom and submissive are widely recognized terms for those partner in the relationship or activity who are, respectively, the physically receptive or controlled participants. Bara male homosexual hentai designed to appeal to men. Sigmund Freud considered foot binding as a form of fetishism. John Stagliano is considered to have started the gonzo pornography genre with his Buttman series of films. A somewhat controversial ejaculation control technique is to put pressure on the perineum, about halfway between the scrotum and the anus, just before ejaculating. Foot fetishism has been defined gay twink porn as a pronounced sexual interest in the feet or footwear. Tentacle erotica can be consensual, but frequently contains elements of naked milf non-consensual sex. Depictions of male anime hentai and female masturbation are common in pornography, including gay pornography. It is also known colloquially as gushing or squirting, although these are considered to be different phenomena in some research publications. Compensating elements of the total dominance and submission are care and devotion complementing one another, thus facilitating stable relationships.