In chapter 15 of Twilight, Bella and Edward go to play baseball with the Cullen family. However, their game is interrupted by the arrival of three nomadic vampires, who are not as civilized as the Cullens. Bella realizes that they are dangerous and tries to hide, but the nomads catch her scent and decide to hunt her. The Cullens work together to protect Bella and fight off the nomads. In the end, Bella is safe, but Edward realizes that their relationship puts her in danger and decides to leave her. The chapter ends with Bella heartbroken and alone. This chapter shows the danger that Bella faces as a human in a world of vampires and the sacrifices that Edward must make to keep her safe.