Piquerism (from the French piquer - "to prick") is a sexual interest in penetrating the skin of another person with sharp objects (such as pins, razors, knives, etc.). Sometimes, this is serious enough to cause extreme injuries or even death. Piquerism is a paraphilia as well as a form of sadism. The most frequently targeted areas of the body are the breasts, buttocks, and groin.
Soviet serial killer Andrei Chikatilo was impotent and could only achieve sexual arousal through stabbing and cutting people with a knife.
Dr. Robert D. Keppel and his colleagues concluded in an analysis of London's Jack the Ripper murders of 1888 that "the injuries sustained by the victims displayed the signature characteristic of picquerism."
American serial killer Albert Fish has been said to have engaged in piquerism upon his victims and his own body, flagellating himself constantly with a nail-studded board. After his arrest and subsequent jailing for the murder of Grace Budd, an X-ray revealed at least 29 needles that were inserted into his groin and pelvic region.
A 25-year old American was arrested in June 2007 for bribing multiple young females with large sums of money in exchange for poking their buttocks with sharp objects.
Elaine O'Hara was murdered in 2012 by a man, architect Graham Dwyer, whose sexual behaviour matches piquerism.