Fastback is pretty much a Cybertronian redshirt. He is a member of the Autobot security forces.
IDW comics continuity
Fastback and Bumper were staking out a potential murder-pit location as part of a wide-net search for Megatron. Megatron and his crew did indeed show up to start up a new round of games, but the two Autobots were discovered by Soundwave and captured, breaking up the party. Once Bumper came to, Megatron killed Fastback by crushing his head to get the point across to Bumper that he would tell him what he needed to know! Megs was kind of completely schizo.
For their sacrifice, Fastback and Bumper got a pretty snazzy and heavily-attended funeral afterward.
- Fastback is pretty blatantly designed to be a pre-Earth version of Outback. However, as Outback had been killed on another planet during the war in the previously-published Spotlight: Kup book, having him die back on Cybertron before the war would have obviously presented problems. One name-change later, a new disposable schmuck is born — to die.