This sounds like "The Bone Season" by Samantha Shannon.
The year is 2059. Paige Mahoney is working in the criminal underworld of Scion London. Her job: to scout for information by breaking into people's minds. For Paige is a dreamwalker, a rare kind of clairvoyant – and under Scion law, she commits treason simply by breathing.
It is raining the day her life changes for ever. Attacked, drugged and kidnapped, Paige is transported to Oxford – a city kept secret for two hundred years, controlled by a powerful, otherworldly race. Paige is assigned to Warden, a Rephaite with mysterious motives. He is her master. Her trainer. Her natural enemy. But if Paige wants to regain her freedom she must allow herself to be nurtured in this prison where she is meant to die.
Although the synopsis does not mention it, seeing ghosts plays a key role in Paige's life. She becomes both conflicted about and a bit too fascinated by her keeper, Warden. It is the first book in what is projected to be a 7 novel series.