Victorian Hearts Series by Laura Kinsale

When her eccentric naturalist father dies on the upper reaches of the Amazon, young Lady Tess Collier sets out to follow his last wishes: return to England and marry well. But Tess, who had accompanied her father on his expeditions since childhood, is as unconventional as she is beautiful.

THE SHADOW Wealthy, powerful and majestically handsome, he is a man of dark secrets--a master of the ancient martial arts of an exotic distant land. Scarred by a childhood of shocking degradation, he has sworn to love chastely... but burns with the fires of unfulfilled passion. THE STAR Lovely, innocent and nearly destitute, she is drawn to him by a fevered yearning she could never deny -- following her enigmatic "shadow warrior" into a dangerous world of desire and righteous retribution.