Rikako (DTB2)

Rikako is a private contractor from the second season of darker than black. She was hired to help escort the main characters without getting caught by the government. Unfortunately, she double crossed our protagonists and goes to sell one of the main characters. Her buyer is killed by a third party who's been tracking her and the main characters. This third party ultimately finds and kills Rikako who's injured after being ambushed by the protagonist.