Erotic literature and pornographic films have been devoted to the sexual uses of glory holes. Fetish cuckolding can have a wide range of expression, from pillow-talk fantasy between monogamous partners to extreme alternative lifestyles, depending on the couple. Masturbation has been depicted in art since prehistoric times and is mentioned and discussed in very early writings. In the 1920s, Havelock Ellis reported that turn-of-the-century seamstresses using treadle-operated sewing machines could achieve orgasm by sitting near the edge of their chairs. Fat fetishism also incorporates stuffing and padding, whereas the focus of arousal is on the sensations and properties of a real or simulated gain. However, that term is usually applied to a male who observes somebody secretly and, generally, not in a public place. Partners can engage in penetrative sex, known as full swap, or 3d hentai choose to soft swap in which they engage only in non-penetrative sex. Bondage is usually, but not always, a sexual practice. Interracial pornographic films have experienced an explosion in popularity, becoming one of the fastest-growing and biggest-selling genres. It is illegal in many jurisdictions. This nude milfs is also the case in many relationships not considering themselves as sadomasochistic; it is considered to be a part of BDSM if it is practiced purposefully. However the genre remains a very small proportion of the pornographic DVD market; for example at porn retailer HotMovies. Human urinal: An act common in the bondage sex community where a male or female slave will serve as a urinal for a dominant partner. In D/S, the Dominant is the Top and the submissive is the Bottom. For example, the Kama Sutra, in particular, goes into specific detail on how to properly strike a partner during sex. A glory hole is a hole in a wall, or other partition, often between public lavatory stalls or adult gaysex video arcade booths for people to engage in sexual activity or observe the person in the next cubicle while one or both parties masturbate.