Seraphim

Winter, 1433 - and Jeanne d'Arc's ashes still glow. In the battle between Good and Evil, the Black Knight's sword fells enemies with silent grace. The Knight has sworn that fallen angel Lucifer de Morte and his cruel brotherhood will pay for their reign of terror over France - and over the d'Ange family, where nearly all have died a terrible death. All but one. Yet the Knight's hard-won battles and dented armor hide a larger secret.
For "he" is actually Seraphim d'Ange. She is traveling to de Morte's demesnes, executing his demon henchmen along the way. Now, aided by Baldwin, a family retainer, and San Juste, a mysterious stranger, Sera grows closer and closer to her final target. Yet little does she know that there is one more aspect of power she herself holds.