A witch, Zero, is searching for a magical tome that can destroy the world…She's guarded by a half-beast mercenary wishing to become human again. They strike a deal: he will offer his protection to her during her journey, and in exchange, she will transform him into a full human when she achieves her goal.
Thirteen and Zero are determined to finish what they started. Meanwhile, they learn more about Thirteen's intentions, including why he chose to become Sorcerer of the State.
Zero, betrayed by Mercenary's doubts about her, dissolves the agreement. Now alone, Mercenary finds himself helping out a young woman with a Beastfallen problem.
Mercenary tries to save Zero from Thirteen, only to have his plans compromised. Meanwhile, Holdem and Albus face their own problems as they try to escape their captors.