Well, after Snow's discovery about 彩音/Junko, I went looking for some albums and found an interesting single. The filename is 青空下的约束-
KAORI-彩音 - PS2版 この青空に約束を 特典CD 「小さなブリリアント-太陽と海のメロディ」
I don't know why Ayane's name is there but it appears Ayane's label is also promoting KAORI's first album here
re;stratosphere .
EDIT: It looks like KAORI did the A side and Ayane did the B side of this single.
Anyway, a little about KAORI....
She did the songs ファーストステップ(First Step), Love Parade, and Lasting in pop'n music.
Apparently she was a part of Shaker Boo.
She is now a part of
Spunky Strider.
The
Japanese Wiki says she has 2 singles and just recently released her first album, re;stratosphere.