Unseen: Chronicles of the Royal Society for Investigation of the Paranormal

Major Gordon Macconnach comes to India at the behest of General Lord Hugh Abington, to be his second-in-command, as well as to put his peculiar talents at the general's disposal. The major is from an old family in the Highlands, which has always had its ties with the Fair Folk. Every generation has borne several Macconnachs with unusual abilities. For Macconnach, it means insight to the realm of death, and the sometimes strange machinations of the supernatural world. For the British Crown, men and women such as Macconnach are a secret in plain sight. Some of these individuals are assigned to military postings, some are spies, and some are diplomats.
General Abington's daughter, Isabelle Alderton, has only recently returned to her beloved India, after attending to her mother through a terminal illness. She has come back, knowing that she is of an age when most other young ladies are already settled into domesticity. The very idea of matrimony is enough to send her into cold fury. Much of the little time she interacts with the officers under her father's command is spent parrying their marriage proposals. And so, she is understandably put off to find Macconnach pursuing her in the dark of night, as she slips out to make an unauthorized visit to a local village.
Quickly, she finds that he isn't like the other preening fools who are his peers. He is dark, strange, and far more insightful than she is comfortable with. After a few false starts, they find themselves launched on an adventure which will upend all of Isabelle's comfortable notions of the world. On the way, in spite of their sparring, they also find themselves drawn to one another in a way neither of them had expected.
If they can survive battling with demons, walking dead, and ancient evil, that is.