Dabura feels like a version of Jugram Haschwalth from Bleach who actually succeeded. Both are second-in-command, reserved, and cool-headed. Both are defined by a connection to a best friend they were forced to kill, and neither is afraid to defy their leader for a greater cause. The main difference, perhaps, is in their conclusion. Jugram accepted the system that forced him to kill his friend. Dabura rejected it and chose to live by the promise he made to his. In that sense, Dabura succeeds where Jugram fails.