I saw K-On.

Tsumugi Kotobuki, K-ON! Wiki

What if K-ON! was a male band? – Otaku House

K-ON Yui Hirasawa and Guitar cursor – Custom Cursor

Is K-ON a seinen? - Forums

K-On! - You know, Ho-kago Tea Time turned into a hardcore rock band so gradually, I didn't even notice. Yeonchi Artist: khyleri Source

k-on! vocaloid crossover by chibicookie602 on deviantART

K-ON!, Hirasawa Yui, Akiyama Mio, Kotobuki Tsumugi, Nakano Azusa, Tainaka Ritsu

K-ON! Yui and Azusa in God of War Mod

K-ON!: The Complete Omnibus Edition (by Yen Press) releases today in the US : r/k_on

K-On! - Pictures