Dantalian no Shoka

Dantalian no Shoka (ダンタリアンの書架, lit. "The Mystic Archives of Dantalian") is a Japanese light novel series written by Gakuto Mikumo and illustrated by G-Yuusuke. The series started serialization in Kadokawa Shoten's light novel magazine The Sneaker on February 29, 2008. A manga adaptation by Chako Abeno started serialization in Kadokawa Shoten's shōnen manga magazine Shōnen Ace on March 26, 2010. Another manga adaptation by Monaco Sena started serialization in Kadokawa Shoten's seinen manga magazine Comp Ace on March 26, 2010. A 12-episode anime adaptation by GAINAX aired between July and October, 2011.

Plot
The young man Huey took over the old mansion of his deceased bibliomanic grand father as well as the book collection that's stored in there. But there was a condition: he also had to inherit the "Bibliotheca".

When he inspects the mansion, Huey discovers a cellar filled with piled up books. In the midst of them he comes across a black-dressed girl who's silently reading a book. She's called Dalian and has a big lock hanging in front of her. She herself is the entrance to the "Bibliotheca of Dantalian" which contains the prohibited "Phantom Books".