Nupperabou

ぬっぺらぼう

Nupperabou (meaning Smudged Face) or Nuppehofu (ぬっぺほふ) or Nuppeppou (ぬっぺっぽう) are a Youkai who appear in the GeGeGe no Kitarou manga and anime franchise. They originally appeared in the Shonen Magazine chapter Korean Magic. Since then, various Nupperabou have appeared, usually as background characters. (Source: GeGeGe no Kitarou Wiki)