Homunculus is a spare time project and tribute to the anime "full metal alchemist". The purpose was completely experimental. The definition of a homunculus decribes a artifical human being. It got it´s origin from the alchemy of the sixteenth-century. Mostly a homunculus is seen as a demonic minion for magical practices.
The idea of homunculus got another meaning in the philosophy of perception: It is seen as another creature in someones mind.