Hiiragi

Hiiragi Masks are a type of youkai that are said to be the spirits of dead children. They are often depicted as wearing white masks with blank faces, and they are said to be able to possess people and make them do terrible things. In the anime Natsume's Book of Friends, Hiiragi Masks are a major antagonist. They are led by a powerful youkai named Hiiragi, who is determined to use the power of Natsume's book to destroy all humans. The Hiiragi Masks are a dangerous and powerful enemy, but Natsume and his friends are determined to stop them. With the help of the book of friends, they must find a way to defeat Hiiragi and his army of youkai. The story of the Hiiragi Masks is a dark and exciting one, full of suspense, action, and horror. It is a story about the power of friendship, the importance of fighting for what is right, and the strength of the human spirit.