Muhyo & Roji's Bureau of Supernatural Investigation, Vol. 13: A New Book of Magic Law

Muhyo and gang discover that the artifact called The Writ of Passage is the key to defeating Teeki...and it's hidden somewhere in their very own Magic Law School! It's not going to be easy infiltrating M.L.S. though, especially with the evil spirit known as Gingko Hag waiting for them!