menpu

A kind of rectangular face covering, typically made of cloth or paper, that is suspended from the forehead via cords to conceal the face and eyes. Sometimes features religious or mystical symbols. Commonly found in Japanese-style fantasy and religious contexts, inspired by Shinto ritual attire and the traditional zoumen (雑面) used in Bugaku (舞楽, traditional Japanese dance).

It is used to hide the face of a deity, spirit, or high-ranking being from be viewed directly by mortals. Or used to prevents a human priest's breath or gaze from "contaminating" the sacred.