Jacob is a hunter and takes out monsters for a living, earning his bread and coin by moving from one town to another. That is just why it is not exactly ideal for him to end up mating with a vampire seductress, a moment of passion in the revelation of what she has done to make things better for those around her coming to a deciding head.
But the deed is done and there is little more that the equine could do but try to understand what's happened, working through the twists and tales of a plan that he does not yet know unfolding around him. And yet he still has a deciding hand in his fate and it's up to him whether he leads himself into the wiles and lusts of the vampire or takes another road entirely...