Both of their family want them to get married as soon as possible even though Mina against it because she doesn't know who is Yoo Jeongyeon is but her family assured her that she have a good personality, kind, responsible and sweet. Process of fall in love with each other.  

your teasing make my heart flutter, 

Your overprotective make me feel save,

Your smile always make my day bright,

Your held my hand and keep my safe,
Your back hug give me warmest that I seek,

Meaning YJYMNS,

Yoo,

Just,

Yoo Mine, Mina 

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