text: The series premiered in Monthly Shōnen Magazine's January 2011 issue, released on December 6, 2010, and has been compiled into eight tankōbon volumes, published between July 15, 2011, and October 17, 2013. Extra chapters of the series have been published in the spin-off publication, Monthly Shōnen Magazine + since 2011 and as of November 15, 2013, they have been compiled into one volume.