Volume one was also number one on Nielsen BookScan 's list of top 20 graphic novels in American bookstores for October 2013 , and for the month of September , the series had more volumes on the list than any other series .
Volume one was # 2 on Nielsen BookScan 's list of top 20 graphic novels in American bookstores for August 2013 , and for the month of September , the series had more volumes on the list than any other series .