A Dear Gazelle
While reading Simon Greene's "Man with the Golden Torc" recently, it occured to me that among the stereotypes and archetypes of fiction - including such characters as Mary Sue - there is the character whose main purpose is to be sacrificed: the Dear Gazelle.
The Dear Gazelle (DG) is a character who is (a) sympathetic and (b) close to the main character (the MC). It's important that the MC loves theGazelle and trusts him or her, because DG is either going to die, or betray MC, or betray MC and die. The narrative purpose of the Gazelle's death is to show the personal cost to the MC, and to introduce an element of pathos and tragedy.
A DG is not a Sacrificial Lamb, because heroes seldom have close relationships with Lambs. Lambs are important to move a story along, raise the body count, and show the seriousness of a situation. But a Lamb's death doesn't have the personal cost of a Gazelle's. Cedric Diggory in Harry Potter was a Lamb. Sirius Black was a Gazelle.
In the Golden Torc, the Gazelle is the protagonist's uncle, a father-figure who must die because he ends up on the wrong side, trying to kill the hero. The hero's girl-friend kills Uncle James so that the hero won't have to.
James Bond's wife was a DG. Bond couldn't afford a wife, professionally or narratively. But a wife who was a Gazelle - that had pathos.
Boromir in Lord of the Rings was something of a Gazelle. He wasn't as close to Frodo as the other hobbits were, but perhaps close enough. I am guessing that if LOTR was written today, Merry or Pippin would be toast.
Other examples of Lambs and Gazelles?