Kim Minju returns to Seoul after her sister receives an anonymous death threat. But little can be done as she lacks the resources and reinforcements necessary to keep her sister safe. Unless she seeks out assistance from Kim Chaewon, who is South Korea's most powerful gang leader, a Tycoon, and her ex, she and her sister are helpless. So will Minju be able to put their differences and past aside for the sake of her sister?

The girl who rejected her years ago is now trying to win her heart.