I was searching on VocaDB, when meeting with a recent cover Ring Suzune. Yes, that's right.
The producer of the channel called Autobahn (responsible for the demo "Sweet Pain"). I think he has his voicebank.
I do not think it's a demo or something because if not more sources would talk. Anyway, what do you think?
The recent cover: http://www.youtube.com/watch?v=Iu7_KMERcoo
I got lost a bit in the categories *