DO anyone know what a title for this story :

Yoona and seohyun is bestfriend . Yoona love luhan so do luhan but they dunno . One day something like luhan and seohyun marry ? Bcz seohyun cant pregenant which is a lie ..... she ask yoona to marry luhan for his sake to get a child ? But actually seohyun does not love luhan she just want yoona suffer and she have affair with yonghwa .

SO DO ANYONE KNOW WHAT THIS STORY TITLE ABOUT ??? I REALLY WANT TO READ IT AGAIN !!! IF SOMEONE KNOW PLZZ INFORME ME ASAP . Thank You

* i already check substitute story but its not that story 

* If i not mistake that story already complete and have only  a few chapter like less than 5 chapter 

ANYONE WHO KNOW PLZZZ LET ME KNOW . THANK YOU