One observation I have of the heroine themes is that, with the exception of Kotori and Kagari, all of them feature only on the common route. The game shifts straight into another genre in the heroine routes where use of the music would be inappropriate. (Though Sizuru's endng theme is linked to hers)
In fact, one can even divide the soundtrack into "common route" and "not-Common route" sides, as one would never hear, for example, Phobia in the former, or DIS IS A PAIN in the latter.
(Did anyone manage to make a mix from Yoshino's lines using Akane's machine?
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