The Vampire's Angel (Realm of the Vampire Council, Band 1)

As Paris devolves into chaos amidst the French Revolution, three lives intertwine.
Xavier, a devout priest, struggles to hold on to his trust in humanity only to find his own faith threatened with the longing he finds for a mysterious American visitor. Thomas fights against the Catholic Church to win Xavier's heart, but hiding his undead nature will threaten the love he longs to find with this abbé. Xavier's sister, Catherine, works with Thomas to bring them together while protecting the family fortune but falls prey herself to evil forces.
The death, peril, and catastrophes of a revolution collide with a world of magic, vampires, and personal demons as Xavier, Thomas, and Catherine fight to find peace and love amidst the destruction.