The term appears to have been first used by the alchemist Paracelsus. He once claimed that he had created a false human being that he referred to as the homunculus. The creature was to have stood no more than 12 inches tall, and did the work usually associated with a golem. However, after a short time, the homunculus turned on its creator and ran away. The recipe consisted of a bag of bones, sperm, skin fragments and hair from any animal of which the homunculus would be a hybrid. This was to be laid in the ground surrounded by horse manure for forty days, at which point the embryo would form. There are also variants cited by other alchemists. One such variant involved the use of the mandrake. Popular belief held that this plant grew where semen ejaculated by hanged men (during the last convulsive spasms before death) fell to the ground, and its roots vaguely resemble a human form to varying degrees. The root was to be picked before dawn on a Friday morning by a black dog, then washed and "fed" with milk and honey and, in some prescriptions, blood, whereupon it would fully develop into a miniature human which would guard and protect its owner. Yet a third method, cited by Dr. David Christianus at the University of Giessen during the 18th century, was to take an egg laid by a black hen, poke a tiny hole through the shell, replace a bean-sized portion of the white with human sperm, seal the opening with virgin parchment, and bury the egg in dung on the first day of the March lunar cycle. A miniature humanoid would emerge from the egg after thirty days, which would help and protect its creator in return for a steady diet of lavender seeds and earthworms. Source: http://forums.narutofan.com/showthread.php?t=145796