Necrophilia is an excessive preoccupation with corpses, death and decay, murders and suicides, funerals and festivals of the dead, and the worship of ancestors and relic-homage. Medically, it is regarded as a pathological symptom and those who indulge in it are considered slightly insane.
Necrophilia specifically refers to coition with corpses, and the first recorded instance of such activity was in ancient Egypt. Several incidences of monks abusing dead women were recorded in the Middle Ages.