Anyone up for a Post apocalyptic team-up?

Extermination seems to be The Odd Couple if it were written by Cormac McCarthy. With seemingly no hope of overthrowing an alien race that wipes out most of humanity a hero and villain team-up as a simply a means to survival.

Do they bicker? Of course.
Do they have any hope? Nope.
Is one messy and the other neat? Probably.
Does one have a potty mouth and the other always reminding about “language”? Yep.
Does the Villian change his ways? Not a chance.
Does the hero maintain his integrity? Find out on the final page!

Was that a spoiler? – watch it “… Language”!