Donghae have fall in love with Jessica for a long ago.It just Jessica never realise about it eventhough there are close.Even if Jessica know it, she can't give any hope to Donghae.How can she give a chance to Donghae if herself have a boyfriend?But it still unlogical , they are still can't be together.The truth is they are siblings. The fact is they are not the true siblings , at least Jessica believed Donghae is her real brother.No matter what , Donghae had promised to his late parents , he won't revealed Jessica's real background.But perhaps he have to ? In order to get Jessica?