I posted this video on Youtube but they don't like it cuz of rights and stuff-_-
I've never seen an entire season of this anime, I should, but always I forgot or something happened and I forgot... but at least the music is really fun and I wanter to share it :)
Cagayake! Girls belong to K-ON, Aki Toyosaki with Yoko Hikasa, Satomi Satou, Minako Kotobuki and Ayana Taketatsu.
I found the song on Bemanistyle.com