Tamakeri (玉蹴り) (lit. ball kicking) is a sexual fetish and sub-genre of pornography within which a man's testicles are abused. The genre is also referred to as ballbusting ("bb" for short). Originally popular in Japan, it has now spread all over the world. Tamakeri is the Japanese term, but it is used by many non-Japanese as well. The dynamics of tamakeri are attacks on a specific part of the male anatomy, the testicles, and the genre appeals to sadist women, as well as to both hetero and homosexual males.
The first wave of tamakeri/ballbusting websites to appear on the internet were sites like Velvet Kick, Tamahimeden (defunct), Spikey Step, Stardeck9 (defunct), Kramtoad, and Femaledom. They often had very poor video quality, made little money, had no plots or stories, and often starring every day looking people wearing masks. They were the pioneers of a then unestablished and unknown area of human sexuality, the expression of which was greatly aided by the anonymity of the internet.
The second wave on the internet were websites like British Bitches (defunct), Vulneraballs (defunct), M-Club-Q, Kinkeri.co.jp (defunct), and Ballbustingworld. Better cameras and camerawork, seemingly higher production values, the introduction of plots or scenarios, much higher range of wardrobes, uncovered faces, better designed websites, and prolific content. The participants of the second wave were more willing to reveal their identity without the need for masks, though masks were often still used.
The third (and current) wave expands on the forms of both the first and second wave, and can be divided into three basic categories: homemade, studios, and social. With the advent of websites which host and sell user uploaded video clips, many thousands of people have created their own homemade tamakeri videos. While these low cost homemade videos became wildly popular through an easily accessed outlet, there emerged even more ambitious and prolific websites, such as ClubDom, which to many set the bar for what a bb studio should be in terms of variety and quality. This wave has also seen several websites which emphasize the social aspect of the ballbusting sexual identity, with forums, chats, and places to post personal experiences. A few examples of the third wave of bb are ClubDom, Ballbustingtube, Ballbustingchicks, clips4sale, and kickedinthegroin.ning.com.