That's the White Tower - the oldest part of the Tower of London - behind Genny. The White Tower is the original square fortress started by William the Conqueror around 1080. Perched on the wall next to Genny are two of the Tower's Ravens. And yes, they play a part in the story.
On the surface, Genny's life seems ripple-free right now. Finn, her sexy boss, has stopped pushing for a decision on their relationship. The seductive vampire Malik al-Khan has vanished back into the shadows. And the witches have declared her no longer a threat. But unless Genny can find a way to break the fertility curse afflicting London's fae, she knows this is just the lull before the magical storm. Then a faeling - a teenage girl - is fished out of the River Thames, dead and bound with magic, and Genny is called into investigate. As she digs through the clues, her search takes a sinister and dangerous turn, exposing age-old secrets that might be better left buried. Then another faeling disappears, and Genny finds herself in a race against time to save the faeling and stop the curse from claiming its next victim - herself!