TheMakaiProject

Sorry for the really late response! We're actually users of the singing synthesizer program UTAU, and the characters we make to go with the voices we record all center around a demonic, angelic, or paranormal theme. We haven't made original songs yet (due to UTAU being made for Japanese vocals), but for now this group is made mostly for artwork based around our characters and links to the songs they cover.

Also: "Makai" (魔界) is the Japanese word for "world of spirits" or "hell", so that's where the name came from. :D