Koropokkur

Historical Background
Koro-pok-guru (also written koropokkuru, korobokkuru, or koropokkur) are a race of small people in Ainu folklore. The name is traditionally interpreted to mean "people below the leaves of the butterbur plant" in the Ainu language (a reference to their small size and lodging).

They were short of stature, agile, and skilled at fishing. They lived in pits with roofs made from butterbur leaves.