Jongin or Kai as what most of his friends love to call him and Mel have been dating for 2 years. But during those 2 years Kai hasn't done anything but to make Mel cry.

He promised not to make her cry.

But he always does.

He promised to never hurt her.

But he did.

He promised to stop his rebelious acts.

But he still continued.

He promised to take care of her.

But he was never there when she needed him the most.

He made promises that were never once fulfilled. 

So Mel decided to stop. She decided to break up with him and leave  just when he finally realized all of his faults.