Similar to events that took place in 0 BBY, Kylo Ren was on a mission to chase down the droid known as BB-8 because he contained sensitive information about the whereabouts of Luke Skywalker. After getting separated from his master, Poe Dameron, BB-8 wandered around Jakku until he stumbled upon a scavenger named Rey. Kylo eventually tracked Rey down and soon discovered her strong connection to the force. They also later grew closer due to their mysterious and unique Force-bond. Rey believed she could lead him back to the light and Kylo was convinced that he could turn her to the dark side where they would rule over the galaxy together. They both continued to resist the other until Kylo heard his mother’s voice calling to him through the force as she was dying, pulling him back into the light and reclaiming his identity as Ben Solo.
Ben joined Rey on the planet Exegol to save her from Darth Sidious and defeat him once and for all (...again). They fought side by side but unfortunately, the effort proved to be too much and took Rey’s life. Ben, also close to death, used his remaining strength to force heal Rey and sacrifice himself to bring her back to life. After sharing a kiss with Rey, he faded away and became one with the force, finally joining the rest of his family.