While Kotori only appears at the end of the actual Idolmaster game, this quiet office clerk of 765 Production is actually a recurring character within the Drama CDs. She is said to be a little older than Azusa, which makes her somewhere in her twenties. Despite not being an idol herself, Kotori loves to sing, which is ironic considering her last name literally means “soundless”.
Another awesome cosplay from Japan Comiket 79! I actually thought she was Suzumiya Haruhi at first, but I saw her name tag “小鳥” which reads “Kotori” in Japanese.
I guess those Japanese self-study lessons are paying off. Thanks to Janet for sending this in!