Karada Sagashi

Look forwards to the ghost story of the red person. "Hey, Asuka… search for my body". At school in the middle of the night, Asuka and her friends search for the scattered body-parts. If they don't find the entire body, the 9th November is repeated and the red person will continue to kill them. Who is the red person? Why is Haruka asking them to search for the body-parts?