Dubious Treasure by Harpie Alexa

She wanted what any other woman wanted, love. He wanted to return home to his most prized possession, his hoard. But fate has other plans. Plans neither of them suspected.

Tommie
She never expected to find love or to have a family of her own. It just wasn’t in the stars for her. Or for anyone really. With humanity half dead, and the remaining elderly males locked away in protective domes, she was one of the last remaining humans left.
The last of humankind, teetering toward the brink of extinction, thriving on today, ignoring the sorrows of tomorrow.
So when Earth suddenly announces its brand new program, the Re-population Initiative, and introduces several mated pairs who had successfully conceived, of course Tommie was ecstatic. For the first time in her entire life, she was given hope for a second chance. But then she got sick and everything changed.

Vaethys
Lured, tricked, and sent to Earth to be a mate, Vaethys does everything he can to avoid fulfilling the deceptive contract he suddenly finds himself bound to. All he wants is to return to Zrestia, to his precious hoard and the deep oceans his heart calls home.
But just as things were starting to go his way, something unexpected happens. He lays an egg.
And if there’s one thing this drakon knows, it’s that he cannot return home without his unexpected mate and their unhatched young.