k-on!!, k-on series, running, multiple girls, nakano azusa, kotobuki tsumugi, hirasawa yui, akiyama mio, school uniform, glasses, tainaka ritsu, 5girls, sakuragaoka high school uniform, long hair, brown hair, black hair, blonde hair, guitar, short hair, twintails, brown eyes, instrument case, guitar case, instrument, couch, parody