K-On! (けいおん!) is a Japanese four-panel comic strip manga written and illustrated by Kakifly. K-On!'s story revolves around four Japanese high school girls who join their school's light music club to try to save it from being abolished. The girls: singer and guitarist Yui, bassist Mio Akiyama, drummer Ritsu Tainaka, guitarist Azusa Nakano, and keyboardist Tsumugi Kotobuki spend their school days practicing, performing, and hanging out together. They form a band, Ho-kago Tea Time (After School Tea Time), which performs the theme songs in the anime.

    Source: Wikipedia