The manga series lasted between December 2007 to July 2012.
Story by Hideaki Koyasu, structure by Daisuke Furuya and art by Yamato Yamamoto who is similar to novel's artist.
The first volume doesn't adapt novel, and second and third volumes precisely adapt the first volume of novel.
Since the fourth volume which Kirihiko appears, every chapter of novel is adapted and split into five or six chapters in the manga.
But many changes are found although the manga generally maintains fundamentals of the novel, for example, manga's "Guillotine" arc has many changes.