The Shadows Between us series by Tricia Levenseller

The Shadows Between Us

They still haven't found the body of the first and only boy who broke Alessandra's heart―and they never will. Since then, all of her relationships have been purely physical. And now at eighteen years old, Alessandra is ready for more. The plan is simple:

1. Make the king fall in love with her.
2. Get him to marry her.
3. Kill him and take his kingdom for herself.

It's no small task, but Alessandra wants a kingdom and is going to do everything within her power to get it. She knows the freshly crowned Shadow King will be her toughest target yet. Shrouded in a mysterious power, no one is allowed to touch him.

But, as forces combine to try and keep Alessandra from earning the king's heart, she wonders if perhaps she's already lost her own.

The Darkness Within Us

Chrysantha Stathos has won.
By hiding her intelligence and ambition behind the mask of a beautiful air-headed girl, she has become a wealthy duchess. And, once her elderly husband dies, she will have all the freedom, money, and safety she's ever wanted.

Or so she thought.
A man claiming to be the estranged grandson of Chrysantha's lecherous late husband has turned up to steal her inheritance. To make matters worse, her little sister is going to be queen and is rubbing it in her face.

Chrysantha decides that the only thing to do is upstage Alessandra at her own wedding. And as for this grandson, he has to go. Never mind that he's extremely handsome and secretive with mysterious powers . . . No, Chrysantha wants Eryx Demos dead, and in the end, a Stathos girl always gets what she wants.