Soul Piper

The Tatarimokke (タタリモッケ) or "Soul Piper" in the English dub, is a demon who was born from the souls of dead children. It plays a flute and stays with the child until it is ready to go to either heaven or hell. The eyes are usually closed, but with wild children (such as Mayu), its eyes will open and send it to hell to become an evil spirit.