Kämpfer (けんぷファー Kenpufā ) is a Japanese light novel series by Toshihiko Tsukiji, with illustrations by Senmu. As of September 25, 2009, thirteen volumes have been published by Media Factory under their MF Bunko J imprint. A manga adaptation by Yu Tachibana started serialization in the seinen manga magazine Monthly Comic Alive on February 27, 2008. An anime adaptation began airing in Japan on October 2, 2009 on TBS.
Plot: The story revolves around Natsuru Senō, a normal high school boy. One day he wakes up to find himself turned into a girl. A stuffed tiger "Harakiri Tora" comes to life and tells him to fight as a female psychic fighter "Kämpfer". Having no idea about what's going on, Natsuru is involved in the battles against other female Kämpfer.
(source: Wikipedia)