Frot

Frot (slang for frottage; ult. from the French verb frotter, "to rub") is a non-penetrative form of male-male sexual activity that usually involves direct penis-to-penis contact. The term was popularized by gay male activists who disparaged the practice of anal sex, but has since evolved to encompass a variety of preferences for the act, which may or may not imply particular attitudes towards other sexual activities. Owing to its non-penetrative character, frot has the safe sex advantage of minimizing the transmission risk for HIV/AIDS; however, it still carries the risk of skin-to-skin sexually transmitted infections, such as HPV and pubic lice (crabs), both of which can be transmitted even when lesions are not visible.

Genital-genital (GG) rubbing is a physically descriptive term for sexual activity in which there is rubbing contact between the genitals, in the same naming convention as genital-anal sex and genital-oral sex. This type of sexual intimacy is not restricted to humans. GG rubbing is a term frequently used by primatologists to describe the act among female bonobos, and is sometimes used in reference to GG rubbing among male bonobos, under the term penis fencing. As such, penis-to-penis rubbing between males is thought, according to various evolutionary theorists, to have existed before the development of hominids into humans and bonobos, and may or may not have occurred in the homosexual activity of both of these genetically related species.

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