Musō (monk)

Muso is the name that a faceless incarnation, born of Naraku's own flesh, took when he was born. He was a violent incarnation who did not know his own name, nor that he was even a demon. Instead, he slaughtered several people in search of a face. Once he had one, he began to wreak havoc in search of some form of satisfaction. Unable to find it he kept slaughtering people, until he saw Kagome and assumed she was what he was after. He possessed Naraku's unnatural ability of regeneration, and fought until Naraku reabsorbed him.

Quote: "Who are you?" "Call me Muso... Yes, that name suits me..."

There is some speculation that that is the name of the man Naraku was before becoming a demon.