A bidet is a bowl or receptacle designed to be sat upon in order to wash a person's genitalia, perineum (taint), inner buttocks, and anus. The modern variety has a plumbed-in water supply and a drainage opening, and is thus a plumbing fixture subject to local hygiene regulations. The bidet is designed to promote personal hygiene and is used after defecation, and before and after sexual intercourse. It can also be used to wash feet, with or without filling it up with water. In several European countries, a bidet is now required by law to be present in every bathroom containing a toilet bowl. It was originally located in the bedroom, near the chamber-pot and the marital bed, but in modern times is located near the toilet bowl in the bathroom. Fixtures that combine a toilet seat with a washing facility include the electronic bidet.

In humans, the anus is the external opening of the rectum located inside the intergluteal cleft. Two sphincters control the exit of feces from the body during an act of defecation, which is the primary function of the anus. These are the internal anal sphincter and the external anal sphincter, which are circular muscles that normally maintain constriction of the orifice and which relax as required by normal physiological functioning. The inner sphincter is involuntary and the outer is voluntary. Above the anus is the perineum, which is also located beneath the vulva or scrotum.