Dick Grayson is a son of a family of Assassins, he was abandoned. Batman found him and raised him as his own and Dick Grayson became Robbin; Batemans sidekick. They fought crime together for years, but then 1 day, Batman betrays him, and Robbin runs away and changes his name to Nightwing. Batman never kills villains; he detains them, but Nightwing kills villains he catches. He's sitting on a roof of a building at night, thinking. As he then hears footsteps beside himself and sees you there