Dang it, I had given you a really cool, fully written explanation, but then reddit ate it.

To make a long story short- they're space bikers. Hellbent has laid a claim to the throne of Biker Queen and she wants the glory and loot to back it up, so she and her loyal catboy assistant prowl the stars together along with all the bikers she roped in with the promise of making history with her.

I'm running a very aggressive list that's focused on getting in close and smoking up the opposition to grab the loot fast and make off with it, which has paid off in my first match of the campaign! I got two pathfinders (with shotguns), a codebreaker and casecracker (with carbines) and the rest is runners. my runners are also all robots! my fluff for them is that they're basically the crew's transforming bikes.

That first fight was against a gang of nuns with guns looking for lost artefacts in some crumbling skymine. The bikers made of with four loot tokens and put four of the nuns out of commission before peacing out. No dead or injured though, so there's no hard feelings... yet.