Mikino is a considerably tall girl with curly black hair that is held up in a ponytail by a green bow on the left side and purplish-blue eyes.
Mikino is usually seen with a normal Kitauji High School uniform for third-year female students.
Mikino is shown to be an outgoing and even-tempered girl who is very friendly to Raina Kitamura that she seems to have a good relationship with her, who is also a bassoonist.
- The name Mikino means "beautiful" (美) (mi), "valuable" (貴) (ki) and "from" (乃) (no).
- Mikino's surname Oka means "ridge, hill" (岡).
- Mikino marched with pom-poms during SunFes, as bassoons are not marching instruments.
|Kitauji High School Concert Band during Kumiko Oumae's first year|
|Note: Section leaders are shown in bold text
1Rejoined the band
2Left the band
3Also in charge of the Tuba and Double Bass sections