The novelization of Star Wars: The Rise of Skywalker has revealed what Kylo Ren's (Adam Driver) parting words were to Rey (Daisy Ridley). Positioned to be the main villain and hero of the sequel trilogy, both characters debuted in J.J. Abrams' Star Wars: The Force Awakens from 2015. Both went through their respective journeys, but kept on finding their way back to each other for varying reasons.
At the end of The Rise of Skywalker, the adversaries came together in an effort to defeat Emperor Palpatine (Ian McDiarmid) - who was able to return following his defeat in Return of the Jedi thanks to cloning. It was obvious that there was a bond between Rey and Kylo Ren from the start, but Rian Johnson's Star Wars: The Last Jedi further solidified their Force connection which provided the foundation for what would be their partnership in the Skywalker saga capper. Following Kylo Ren's emotional conversation with Han Solo (Harrison Ford) in light of the death of his mom, Leia (Carrie Fisher), he rushed to Exegol to help Rey take on Darth Sidious. And to make up for everything he's done, he willingly sacrificed himself to ensure her survival.
After Kylo Ren's return to the light, he didn't have any time to even talk to Rey about their win since he died shortly after, but The Rise of Skywalker novelization (via CBR) from writer Rae Carson reveals his final words to her: "A voice came to her through the Force, clear and strong. 'I will always be with you,' Ben said," the book excerpt reads. Meanwhile, Rey had a reply that echoed a familiar sentiment - "She smiled. Let the truth of it wash over her. 'No one's ever really gone,' she whispered."
Another controversial interaction between Rey and Kylo Ren revolves around the kiss they shared following Palpatine's defeat. Since there was barely any discussion about it after, it became an element of The Rise of Skywalker that was open to people's interpretation. Those who were rooting for the pair to have a relationship read it as wish fulfillment, but the same novelization says otherwise, calling it a "kiss of gratitude" instead. Assuming that Abrams and co-writer Chris Terrio never intended the scene to be romantic, it's curious why they even put it in the film in the first place since it was bound to cause some confusion.
Since copies of Star Wars: The Rise of Skywalker novelization have been distributed, fans have been learning new information about the film. It has also served as a great tie-in content to explain some of aspects of the movie that were either unclear or simply overlooked. Some might argue that a few details from the book that was omitted from the movie should've been included like this aforementioned bit, which would've worked well since they opted to not have a Ben Solo Force ghost in the end.
Source: Star Wars: The Rise of Skywalker Novelization (via CBR)