k-on!!, k-on series, running, multiple girls, akiyama mio, glasses, nakano azusa, school uniform, brown hair, tainaka ritsu, black hair, instrument case, guitar case, long hair, sakuragaoka high school uniform, brown eyes, hirasawa yui, 4girls, kotobuki tsumugi, guitar, 5girls, short hair, extra, couch, parody, bag