Triple Flames by Alyse Zaftig

Have you ever had baby fever?

I do. And if I don’t have a living child by midnight of the day that I turn 30 years old, I’ll die. As the prince of Ganamarsia, I have a duty to my people. Long ago, someone cursed the royal line so that the heir would die if they did not fulfill their obligation to their people after a civil war nearly tore the planet apart.
My two wingmen, closer to me than brothers, swear that they will die, too, if I perish. All three of us will die if I do not have an heir. Soon.

I’ve been presented with every eligible female on this planet. I’ve traveled the galaxy to find a suitable mate and found nobody who could possibly be our mate. Until a small, curvy human from Earth arrives on a small spaceship.
Love at first sight. I thought it was a myth. I thought it was a fairytale. Until it happened to us. Now we’ll stop at nothing to convince her that she’s ours.