Hector and Cassandra have never slept together. (Those are not their real names: he tames drones and her foresight is computational.)
What joins them is stronger than lust and bleaker than love, and it's not, quite, defeat. They have never met except in cities under attack. He coordinates their defense with bravery and skill. She scouts the future and comes back with warnings. They are heroes. They win impossible battles.
They know with certainty that the city they defend is already lost. They are surprised, every time, that in their hearts there is still something that can break.
To talk about this thing they choose with dull consistency to do time after time would be another way of failing for a temptation they don't feel. But it is a choice. Their bosses' bosses are the bosses' bosses of the attacking forces, and more than once they have been offered a transfer to the other half of the Urban Warfare Research Lab. Every time they refuse, always with lies, always not knowing what the true answer would be. So they keep meeting among the ruble of cities that think themselves at war, resistance heroes until at last they open the abstract doors of their careful strategies and walk away from the burning towers without looking back.