A Rose For Everafter was Castle's second bestseller after In a Hail of Bullets, probably also at least partly written while he was still at college. It is one of his 'standalone' books, not part of the Derrick Storm series. Although referenced in the show, it has never been made available in the real world.
(from richardcastle.net) At the Blessed Sacrament School for Girls, Sister Mary Grace leads her young charges in daily Morning Prayer, asking the Lord their souls to keep. But the young women of Riverbend are starting to disappear, only to be found in shallow graves, wrapped in shrouds of white and grasping a red rose in their cold dead hands. Who could be killing the town's virgin daughters? And why is he burying them alive? When Sister Mary Grace starts investigating, she discovers a trail of evidence that leads from the local rectory to the upper echelons of the archdiocese – and ultimately to a secretive organization whose provenance may be very far from godly.
References in Episodes
The novel features in and gives its name to episode 2.12. In the episode, Ryan reveals that the book was Castle's second, and Esposito observes that it is dedicated to Castle's college sweetheart, Kyra Blaine. The dedication reads "You make the stars shine." Later in the episode, Kyra tells Beckett that Castle only dedicates his books to people he really cares about.
It is also seen in Kyle's apartment in episode 1.1.