William Minerva is the owner of all the books that are currently available in the library of the Grace Field House.
|• Professional Status•|
|Affiliation|| Plant 3 (Formerly)|
|Previous Affiliation||Grace Field House|
|• Personal Status•|
William Minerva's face is never revealed in the manga and it is not even known to the public is he is alive or not. But some little things are known about his appearance. He is a tall man, who is almost always seen wearing a gray suit with a gray hat.
Phil discovered that all the books contain some kind of secret message in them. Telling the children to ''run from the house, because there is danger''
William Minerva also left a pen behind for Sister Krone with the initials ''WM'' on it, implying that the initials are his.
It is currently unknown why he left the books with the secret message in them behind and why he left a pen behind for Sister Krone.