When Severus Snape is killed by Voldemort later in the story , Harry realizes that Snape was not the traitorous murderer he believed him to be , but a tragic anti-hero who was loyal to Albus Dumbledore . When Voldemort kills Snape later in the story , Harry realizes that Snape was not the traitorous murderer he believed him to be , but a tragic antihero who was loyal to Dumbledore .