Regarding Aichan's Manager..
Yes, i think most likely is a guy..and yea..like what
SNIPER mention that his hair is just near his shoulders
It's not very clear, but ~12:50 onwards, Aichan pass her handphone to a guy whom i believe is her manager..he should be the same guy in the [Aichan's Man scream] video that
KaitoDoraemon post (1:37).
http://www.youtube.com/watch?v=x1gu_ZQmQd8
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If still wanna know how he look like..I believe this is the guy..
[Collabo Labo (2009.02.04) Morning Musume + TRF](watch the video, it will be much clearer)
He appear quite a few times..and also the one who walk in together with Aichan and Gakisan when it's Aichan turn to rehearsal for her Duet song with Yuki..(unless he's gakisan manager, but it's quite sure gakisan manager is stou san alr)