Often, strong views are expressed with regard to anal sex; it is hot gay sex controversial in various cultures, especially with regard to religion, commonly due to prohibitions against anal sex among gay men or teachings about the procreative purpose of sexual activity. The arousal from being desperate comes from the sensation of having a full bladder. Typically featured are hitting, choking, name-calling and hair-pulling. The prostate gland is one of the organs that contributes fluid to semen. For legal reasons, the vast majority of so-called reality porn involves professional actors and actresses posing as so-called amateurs. Men may also rub or massage the glans, the rim of the glans, and the frenular delta. It is sometimes combined with BDSM features. Group sex most commonly takes place in a private sex party or semi-public swinger gathering, but may also take place at massage parlors or brothels or, in some jurisdictions, at purpose-built locations such as sex clubs. Bondage/BDSM Bondage pornography gay hentai features performers tied horny milfs up or constrained in various ways. Foot fetishism has been defined as a pronounced sexual interest in the feet or footwear. Macrophilia is a fascination with or a sexual fantasy involving giants, more commonly expressed as giantesses . As of 2013, little analysis of this paraphilia has been reported in medical literature. Other objects such as ball point pens and thermometers are sometimes used, although this practice can lead to injury and/or infection. Although interracial pornography theoretically can apply to depictions of sexual activity between performers of any different racial groups, the term is most commonly used for heterosexual sex acts between black and white performers. Terminology for roles varies widely within the various BDSM subcultures. Sub-genres can also be classified into the characteristics of the performers or the type of sexual activity on which it concentrates, and not necessarily on the market to which each sub-genre appeals.