Tamakeri (玉蹴り)(lit. ball kicking) is a sexual fetish and subgenre of pornography in Japan. In tamakeri pornography, a female kicks a man in the testicles, which sounds and looks quite odd for Western viewers. Some tamakeri fetishists report that they prefer to witness kicks that resound with a hearty slap. Pornographic Tamakeri videos cater to masochistic young men for whom the idea of getting their testicles kicked is sexually stimulating, at least in fantasy.
Erika Nagai is among the many AV performers who work in this kind of fetish.