exhibitionism

Exhibitionism is the act of exposing in a public or semi-public context one's intimate parts – for example, the breasts, genitals or buttocks. The practice may arise from a desire or compulsion to expose themselves in such a manner to groups of friends or acquaintances, or to strangers for their amusement or sexual satisfaction, or to shock the bystander. Exposing oneself only to an intimate partner is normally not regarded as exhibitionism.