The seven Blu-ray disc volumes of K-ON! have an extra short anime "Ura-ON!"

Sentan Island is a small island surrounded by the Yuden Sea. It exists in a state of dreamlike tranquility, cut off from the war between the Northern Government and the Southern Continent Free Zone. Our hero, Akiyuki Takehara, lives on Sentain Island along with his mother Fusa. He is currently separated from his father, the town doctor Ryuzo, but the bond between father and son remains. One day, after taking Ryuzo the lunch that Fusa has made for him as usual, Akiyuki arrives at school, where he is caught up in an explosion along with his friends, Haru and Furuichi. The explosion produces a mysterious light, which enters Akiyuki's arm, causing him excruciating pain. He's given no time to understand it, however, as the white-haired girl who rode on the bus with him guides him to a power unlike anything he's ever known.

Labyrinth Town is a legendary city composed of ten districts, home to witches and diviners alike. In the outermost district of this maze, many young girls begin training to join the ranks of the "Urara," a group of women known far and wide for their ability to divine the answers to the world's most difficult questions. Chiya, a wild girl raised amongst the animals in the mountains, is invited to take her rightful place as a first rank urara. By joining them, she hopes to divine the location of her long-lost mother. Chiya quickly makes three friends: studious Kon Tatsumi, aspiring witch Koume Yukimi, and reticent Nono Natsume. Armed with only their own ingenuity and a vague connection to the gods, they begin their journey in the way of the urara. [Written by MAL Rewrite]