Junko has bob-length dark teal-green hair and turquoise eyes.
She is normally depicted in the standard Kitauji female third-year uniform.
Junko is a playful and friendly girl who is often depicted playing games with other clarinetists.
Junko is very close friends with Yumina that they are often depicted hanging out or talking together.
- The name Junko means "pure, clean, simple" (純) (jun) and "child" (子) (ko).
- Junko's surname Koshigawa means "surpass, cross over, move to, exceed, Vietnam" (越) (koshi) and "river, stream" (川) (kawa/gawa).
|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