Parasyte is a science fiction horror manga about a teenage boy named Shinichi Izumi whose right hand is taken over by a parasitic alien creature called Migi. Unlike other parasites that fully consume human brains and take over their bodies, Migi only partially infects Shinichi, leaving his mind intact. The two are forced to coexist and communicate, forming an uneasy alliance to survive against other, more hostile parasites that hunt and kill humans. The story explores themes of humanity, identity, and the nature of life as Shinichi and Migi face violent battles and moral dilemmas. Readers enjoy it for its intense action, deep philosophical questions, and the unique relationship between the human host and his alien partner, as well as its gruesome yet compelling art and suspenseful plot.