Princess x Assassin

But in this tale, the assassin works for her. She wants the throne so she can protect her kingdom from her corrupt siblings. To do so, she must be both pure-hearted and cunning. At first, the only support she receives is from House Valderis through its heir, the master assassin Astran Valderis. The princess will win over those she can, and Astran will slay those she can't. Together, they will obtain the throne.