Red’s Mate by Carolyn Faulkner

In the aftermath of the wars, pestilence, and famine that devastated the land, mankind – and its genetically superior counterparts – huddled together in what passed for civilization. Small bands of cutthroats and thieves roamed the landscape, although there was the occasional enclave; small villages, some better organized compounds, and even sometimes a decently run city-state, but they were by far the fewest and farthest between.

It was in a very tiny village that the Omega Ebby had grown up, surrounded by women who knew what she would become, as well as a few men to whom she was unattractive, all of whom participated in training her to defend herself. They had also all vowed to protect her with their lives.

And in the end, because of him, that was exactly what they had done.
Ciaran, an Alpha born in one of those more successful city-states, had risen through the ranks of what passed for the Army to command a battalion that combed the wasteland; defeating enemies, making the occasional ally. Their military mission was to collect whatever might benefit them immediately – or the base, when they returned. But he was conducting a mission of his own for that which he had wanted all his life: an Omega on which to breed sons.

They had received intelligence that there was something very valuable hidden in a village not far away.
And there was.
Ebby.