The Mystic Archives of Dantalian (Dantalian no Shoka)
Full name: The Mystic Archives of Dantalian (ダンタリアンの書架, Dantalian no Shoka, lit. "Bookshelf of Dantalian"; alternate title Bibliotheca Mystica de Dantalian)
Written by Gakuto Mikumo
Illustrated by G-Yuusuke
Published by Kadokawa Shoten
Imprint Kadokawa Sneaker Bunko
Magazine The Sneaker
Original run February 29, 2008 – February 28, 2011
This story takes place in England after World War I. After the death of his grandfather, Hugh Anthony Disward, also known as Huey, receives a mysterious key and according to his will, must take custody of the Bibliotheca Mystica de Dantalian in order to inherit his estate and all his possessions. Upon meeting Dalian, a child living at the estate, he learns that she is the guardian of the Archives which contain forbidden knowledge stored in thousands of magic books called "Phantom Books" (幻書, gensho). Upon agreeing to become Dalian's new Keykeeper, Huey joins her into investigating incidents regarding people misusing the power of the Phantom Books, most of them with tragic consequences, and using his power as Keykeeper to seal the power of the Phantom Books and restore order to the area.
Interesting, the blurb make it seems similar to Gosick, is it ?
@Raitoiro I would definitely say there were similarities, I would recommend this one if you liked Gosick and vise versa.
This is one I wanted to read sooooo much back when the anime aired, I'm totally in for this.