Marie Brennan 
In Ashes Lie [EPUB ebook] 

ABOVEIt is the seventeenth century. For twenty years, the City of London has been torn apart: by war, by plague, by fire.BELOWThe Onyx Court is London’s faerie shadow. Dedicated to co-existence with mortals, it struggles to survive against rival courts who oppose everything it stands for.BETWEENNow, when these two realms are at their most divided, they face a threat neither can defeat alone. The Great Fire ravaging London is more than mere flames. While the city’s human residents struggle to halt the inexorable blaze, the fae must defeat a stranger foe: the embodiment of the fire itself, a monstrous Dragon that seeks to devour London both above and below. If the faerie queen Lune and her mortal consort cannot bring the two worlds together, the city itself may not survive . . . .