 is a manga written and drawn by Kiyohiko Azuma, and published in Japan by ASCII Media Works in the monthly magazine "Dengeki Daioh".Eighty-two chapters have been published; 81 of these have been collected in twelve "tankōbon" volumes, with further chapters appearing in "Dengeki Daioh" to be collected in "tankōbon" format over time.The series was licensed in English by ADV Manga, with five volumes published; volume six was scheduled to be published February 2008 but was delayed indefinitely.