User blog comment:Hitsuji Mamoru/Servant Creation Room 2 : Guess of the Who/@comment-30314236-20170329170644/@comment-4802891-20170401152423

You will have to give another hint Shiki, because I have scavenged everything I could regarding urban legends that are more or less associated with the themes of Halloween and I can't find a good match.

For the "Hanged ???" skill, which seems to be a big hint point, I have found cases of hanged persons thought to be Halloween decorations, but they aren't associated with a specific character. I have also found the dog of the Hanging Hills but since he is humanoid, this is ruled out as well.

Your character is pretty hard to guess, or I am just lacking knowledge of American legends.