A spin-off of the Partnership in Blood series.

By the time the alpha of the Morvan werewolf pack approaches l'Institut Marcel Chavinier for help solving his people's fertility problems, pack numbers have dwindled and the remaining members are desperate. Though the wizards at l'Institut have no experience with werewolves, their lore, or their brand of magic, Raymond agrees to help.

At l'ANS headquarters, Raymond finds Marc Gourlin, a young wizard fascinated with werewolves. Marc agrees to visit the werewolves' home to study their rituals for the source of the problem. But when he arrives, he finds himself distracted by Adenet Silaire, the pack shaman. The attraction between them is powerful, but though Marc suspects he might be Adenet's mate, Adenet rebuffs him. Marc is a man, and Adenet's sense of responsibility will not let him take a male mate when the pack so desperately needs children.

Meanwhile, Jean and Raymond discover the Aveu de Sang allows a vampire's Avoué to calm his inner beast. For Jean and Orlando, this is wonderful news—but it only convinces Thierry how much Sebastian is missing out on because they cannot form an Aveu de Sang. Determined to give his partner everything he can, Thierry sets out to recreate the bond denied them by Sebastien's past.