|Akiyama Mio秋山 澪A|
|Measurements||Height: 160cm, Weight: 54kg|
|Hair||Black, Blunt Bangs, Hime Cut, Long, Sidehair, Waist Length+|
|Body||Left Handed, Pale, Slim, Teen|
|Clothes||Knee-high Socks, Miniskirt, Ribbon Tie, School Uniform, Shimapan|
|Personality||Mature, Serious, Shy, Watashi|
|Role||Bassist, Childhood Friend, High School Student, Honor Student, Musician, School Music Club Member, Singer|
|Visual novels||Main character - K-OFF! ON!!!|
Protagonist - K-ON Galge!? -Mio to Ritsu-
Protagonist - K-ON Galge!? -Mio to Yui-
Protagonist - Mio Aji!
Main character - Mio-chan to A-so-bo
Mio is a shy girl who is in the light music club. She plays a left-handed, 3-Color Sunburst Fender Jazz Bass with a tortoiseshell pickguard, though is shown playing a Fender Precision Bass in the first manga volume. While she originally intended to join the literary club, she was forced into the light music club by her childhood friend and the club's president/drummer, Ritsu.