MF文庫J
is a Japanese light novel series by Toshihiko Tsukiji, with illustrations by Senmu. The series contains 15 volumes published by Media Factory under their MF Bunko J imprint between November 2006 and March 2010. The main series covers 12 volumes, while the remaining three are short story collections. A manga adaptation by Yu Tachibana started serialization in the April 2008 issue of "Monthly Comic Alive". A 12-episode anime adaptation aired in Japan between October and December 2009 on TBS, concluded in 2011 with "Kämpfer für die Liebe".