K-On! (Japanese: けいおん!, Hepburn: Keion!) is a Japanese four-panel manga written and illustrated by Kakifly. It was serialized in Houbunsha's monthly seinen manga magazine Manga Time Kirara between the May 2007 and October 2010 issues. It was also serialized in Houbunsha's magazine Manga Time Kirara Carat. The manga relaunched from April 2011 to June 2012 with two separate storylines published in Manga Time Kirara and Manga Time Kirara Carat. The manga is licensed in North America by Yen Press. A spin-off manga about a different band of high school girls, K-On! Shuffle, began serialization in July 2018.