Upon The Threshold April Zyon Zyon April by April Zyon [zyon, April] B00YAZB4KG instant download after payment.

Chief Scientist Elisabeth Washington and her people have fled a ravaged Earth in search of a new life. Finding a world to suit isn’t easy, the journey long and arduous. When they finally set foot on what they hope will be their new home, they're jubilant, overwhelmed with relief. Too late, much too late, they discover what no one predicted: they have neighbors.
The Droushan, a shapeshifting race, have their neighboring worlds under their protection. When one of those worlds suddenly comes to life, Sect Leader Kraven and his best friend, Weapons Master Lukkis are sent out to learn what's happening. They not only find a world reborn but an extraordinary woman who excites and arouses their mating urges.
Three intelligent, capable leaders intent on protecting their people. Two big, powerful men, working to control their inner beasts. One brilliant woman who wants them and can't understand her own urge to submit to whatever they want to do with her. It's a tense first contact situation and these three are living upon the threshold.