The back side of the Kumano-goo distributed by Kumano Sanzan (three major shrines, Kumano Hongu Taisha Shrine, Kumano Hayatama Taisha Shrine and Kumano Nachi Taisha Shrine) was used for kishomon (sworn oath) from the Heian period through the early-modern times.
熊野三山で頒布される熊野牛王は、平安時代から近世には裏面が起請文に用いられた。