K-On!(けいおん!Keion!) is a Japanese four-panel comic strip manga written and illustrated by Kakifly. The manga was serialized in Houbunsha's 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. A 13-episode anime adaptation produced by Kyoto Animation aired in Japan between April and June 2009. An additional original video animation episode was released in January 2010. A 26-episode second season, titled K-On!! (with two exclamation marks), aired in Japan between April and September 2010. An anime film adaptation has been announced. The title of the series comes from the Japanese word for light music, keiongaku(軽音楽), but in the Japanese context is similar to pop music.