Yobuko (Calling Child) is a youkai from the GeGeGe no Kitarou anime and manga series. In the manga, he was sometimes depicted as a member of the Kitarou Family. He has also been referred to as Yamabiko (山彦, lit. Mountain Echo) or Yama-Kozou (山小僧, Mountain Boy). (Source: GeGeGe no Kitarou Wiki)