He's not literally a devil, he just acts like one. Kim Jongin or Kai, is your typical bad boy where in the words arrogance, coldness and selfishness suits him best; making fangirls of his go crazy for him and Krystal was never an exception. Jung Soojung, mononymously known as Krystal, is the girl with standards higher than her heels and rejects every bit of her suitor in every possible way she can but turns to the other way around the moment she met Kai. And then there's Lu Han, Krystal's cousin from China, who has trouble with commitments and confuses everyone whether he's a boyish girl or a girlish boy.