My Devil Sister

Born into an ancient witch family, Lovett possesses striking beauty but bears a cruel destiny: each of her boyfriends must undergo a "test of true love" by her older sister, Vine. Those who succumb to temptation become sacrifices, their lifeblood drained by Vine to fuel the family's magic. In reality, Lovett was never a protected heiress, but merely a tool used to attract men and maintain the family's power.