Bound to the Beast by Grace Goodwin

He’s a warlord on the edge. She’s a teacher on the run. Their worlds are about to collide—in the most explosive way possible.
Warlord Iven has one foot in the grave, days away from a ceremonial execution to save his honor—and the galaxy—from his untamed beast. But when a desperate plea lands a mission in his lap, everything changes. A royal child is in hiding. Assassins are on Earth. And his last chance at redemption lies in a sleepy little town in Washington… in the form of a fiercely protective, infuriatingly sexy fourth-grade teacher named Krystal.

Krystal James has already lost everything. Her sister. Her old life. Her peace. Now, she lives under a false identity, guarding her nephew—the last heir to an alien fortune—with nothing but grit, lies, and a very protective alien cat. Falling for a towering kindergarten teacher with a lethal growl and a gaze that says mine? Not part of the plan.

But fate doesn’t care about plans. It only cares about destiny.
When Iven’s beast roars to life, Krystal must decide: trust the alien protector with her body and heart—or risk losing everything to the killers closing in.
Because once an Atlan warlord claims his mate, there’s no turning back. And this beast has found his match.