SF-A2 Miki, or just Miki, is a Vocaloid. Her purpose is to sing songs beautifully, but her robotic voice prevents emotional inflection. She has the appearance of a robot who wanders around pondering her existence, trying to figure out what it means to be human and attempting to emulate human emotion and philosophy, to numerous degrees of failures. She was created by an unidentified person known only as "F.F.," who later disappeared, leaving Miki to herself to try and find her place in the world.