The exclusive bonus material in the e-books includes
sketches, fan art, location photos and "outtakes".

+ 36 pages of bonus material. Buy e-book: English | French	+ 36 pages of bonus material. Buy e-book: English | French
+ 46 pages of bonus material. Buy e-book: English | French	+ 41 pages of bonus material. Buy e-book: English | French

Volume V and Volume VI are currently in progress.