a Momonjii is a yokai found in the folklore and mythology of Japan.
Upon reaching an advanced age the yokai known as Nobusu will evolve into one of two possible forms, either a Yamachichi or a Momonjii.
A Nobusu resembles an ugly, hairy old man who will attack those that displease him as well as spread a supernatural wind that causes any who get caught within it to grow extremely sick.