Seems like another Yameii-esque situation, or "Musician creates an avatar and uses a heavily-modified vocalsynth to represent her". They might also be combining a Vocaloid vocal with vocals from other synths and maybe even their own. In this instance, though, she just sounds like a Vocaloid bank making heavy usage of the Growl and Air parameters. I can't quite pinpoint whose voice that is underneath, though...
VocaVerse Network
peaches2217
WyndReed
She sounds kinda like Luka at parts, but like another loid at others. :/
Ronny777
I'm 99% certain that that's mainly AMY's Voice bank but modified like @peaches2217 said. Just the way the pronunciations of the words sound. The raspy ness of the (u:)s and (aI)s. I played around in V5 and I could get her to sing in the same timber at C4.If its not AMY I'm really curious what Vocal synth it could be. I'm certain she was tuned in V5 because of the breaths and the vocal fry effects.
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Actually Ive seen quite a bit of these musicians creating avatars in this style, favoring Amy, as of late, saw another like this the other day, I will dig fr her later.