Among Shadows and Crowns

Aster is an assassin. Since she was a child she was trained to be a hones weapon. When she is given the task to kill the king, things get a little crazy.
Maxon is a prince with an affinity for fire. His father banned all use of magic when he came to rule, when Maxon is tired of hiding he decides to hire somebody to kill him.
Arden is a assassin like Aster, they grew up together. When he hears about Aster working with Maxon you could say he's a little concerned