I am unsure. All I know is in IV one of the female tracks (the dominatrix sounding one) sounded like it's the voice actress for Cullen from CODE GIEAS. Sadly the voice actress went off to do random female voices for SKYRIM like Jordis, Ysolda and a few other female characters.
I'm pretty sure it Jenny, Ami from Hi Hi Puffy AmiYumi, Ichigo's sister Yuzu from the Bleach dub. I haven't looked anything up to prove it but all of them (and the CAS voice) sound exactly the same to me.
Minna! Chiruno no sansuu kyoushiitsu hajimaru yo! Atai mitai na tensai mezashiite, ganbatte itte ne!