Bjurman is a lawyer and Salander's guardian after Holger Palmgren has a stroke. He rapes Salander brutally in Tattoo, but she records the rape and is using it to keep him under control until he can get her out of guardianship. When he decides to have her killed, connecting Zala and Salander, his purposes in the saga are fulfilled and he can exit – with a bullet to the head, courtesy of Ronald Niedermann. Salander is seen as the chief suspect in his murder.
For more on Bjurman, see our discussion of him in The Girl With the Dragon Tattoo.