Shamiko, also known as Shadow Mistress Yuuko, is on a mission to save her family from the Clan of Light's curse. She develops an odd alliance with Momo, a competitor from the Light Clan, along the road! They'll have to work together to track down another magical girl who has inexplicably vanished, and what is this? Shamiko's mystery father could be closer than she believes, and there's a menacing power hiding somewhere in the city.