The Emperor's Conspiracy (Regency London #1)
Michelle Diener

Chance led to Charlotte Raven’s transformation from chimney sweep to wealthy, educated noblewoman, but she still walks a delicate tightrope between two worlds, unable to turn her back on the ruthless crime lord who was once her childhood protector.
When Lord Edward Durnham is tapped to solve the mystery of England’s rapidly disappearing gold, his search leads him to the stews of London, and Charlotte becomes his intriguing guide to the city’s dark, forbidding underworld. But as her involvement brings Charlotte to the attention of men who have no qualms about who they hurt, and as Edward forges a grudging alliance with the dangerous ghosts of Charlotte’s former life, she faces a choice: to continue living in limbo, or to close the door on the past and risk her heart and her happiness on an unpredictable future.