Overdue by Elizabeth Spann Craig

Carmen King is a busy woman. Not only does she sit on the library board and dabble in the Friends of the Library, but she juggles quite a few relationships at once. Apparently, this doesn't go over well with at least one of her boyfriends—Carmen is found dead at the bottom of the library staircase.

Librarian Ann Beckett not only finds Carmen's body, but finds herself entangled in Carmen's mysterious death as she sets out to learn why Carmen's death, from the killer's perspective, was overdue.