I have a VoiceLive 2. And while it is an extremely versatile and powerfull vocal processor, I don't think you will get the result you want. As far as I'm concerned the generated voices are only believable when they're placed in the mix with the lead voice. When you listen to the generated sound only you will notice some digital artifacts and tiny strange pitchbendings a human voice wouldn't make.

If you want a believable female voice you would have to let a woman do the talking (Oh, wait. I can see the snag there )
If it is more of a comic sketch you could use your falset voice.