Homunculus

Nakoshi Susumu, a 34-year-old man living out of his car, is approached by an unsettling medical student who offers to pay him a significant sum to participate in a trepanation experiment. The procedure, which involves drilling into the skull to access a sixth sense, seems too unusual for Nakoshi to accept, but when his car is towed, he agrees to the operation in exchange for cash. Initially, the experiment appears to have no effect, but Nakoshi soon discovers that his left eye is now able to see a twisted, homunculus-like figure within every human, revealing a dark truth about the nature of humanity.