Among female demon masks called "Hanya [female demon] masks," the one which almost became a snake with the worst karma is called Shinja.
「般若の面（はんにゃ）」と呼ばれる女の鬼の面の中でも、もっとも罪業深く、ほとんどヘビになってしまった面を真蛇（しんじゃ）と呼ぶ。