Her Vengeful Embrace by Katee Robert

Amarante took on the moniker Death fifteen years ago and in that time, she’s more than earned the title as part of her long quest for justice. Now, with her plan finally reaching its culmination, she’s putting everything on the line. And she won’t let anyone stand in her way—especially the one man she lost her heart to, once upon a time.
Tristan Merrick gave up being a hero along with his other childhood dreams. He knows how the world works now. Power is the only currency that truly matters, even if he has to compromise every bit of himself to gain it. His only regret is betraying the one woman who made him question it all.

Fate and revenge have put Amarante on a mission she doesn’t expect to survive…and Tristan stands directly in her path. The chemistry that bound them together before sparks even hotter now, with both of them helpless to resist. But with the stakes higher than ever, will Tristan repeat the sins of the past… Or will he do whatever it takes to save Amarante from herself?