After the massacre in Ukishima, Saya loses her memory and wanders the slums until she meets Haru, an unlicensed doctor, and Ran, the girl who hunts the Elder Bairns. As her memory returns, she discovers that she had relationships with them both in the past, and secret promises made by the Nanahara clan and her nemesis, Fumito. As Sayo tries to rescue kidnapped Haru, she encounters Fumito again.  This feature untold story in the time period between the 2011, 12-episode TV anime created by Production I.G and Nanase Ohkawa (CLAMP), and its feature film sequel Blood-C: The Last Dark in 2012.