Su is right. This book has double meaning. One meaning is the same as described by her. Another meaning refers to the character inhabiting the dead soul and experiencing the vivid feelings of the deceased. It is a dark fantasy book as you must be knowing since you are reading it.

If you are 'dead set' on doing something it means that you are absolutely determined to do it. As this is a book title, I suspect that there is a double meaning in there somewhere.

Definition: firmly decided or determined; resolved: Examples: His family was dead set against the marriage. he is dead set against going to Spain. That's why both parties are dead set on amending it. The medical consensus is dead set against creating heritable genetic alterations. Part of the problem was that her lawyers were dead set against her writing anything that characterized her testimony.

Who was he'd militants in positions Extremism in Opinion