They both have wounded heart cause by each other's past Will they be able the heal each other by getting back together? Or it will just lead to another wound in their heart?  

They are living in a happy and perfect married life together. Everyday is full of love and happiness between, they are living in perfect marriage. But when circumstance arrives how strong they are to protect their relationship, to be together, how strong the love the feel for each other. What if something happen that makes everything restart from the beginning?   this is the continuation of the story of Lee Donghae and Park Hyerin in "Hyung's little sister"

A secret agent who only knows to do his job, he complete his task given to him without failing. He is the top agent of his organization. In his one mission he will encounter a girl without a name and have a mysterious background. Now he must protect her life against the black organization that is hunting her while figuring out who she really was to solve the case.

Park Hyerin is the little sister of Park Jungsu also known as Leeteuk of super junior 12 years studying abroad she came back to Korea. An accident happen that lead Leeteuk's to decide to drag his sister to live with him at their dorm. Living in a house with full of crazy boys will make Hyerin turn her whole life upside down especially when you're living with a not so prince like Donghae and having evil maknae as your bestfriend.