You do not fall for a nice decent guy who loves you since ages but fall for a player because you feel he’s changed although he humiliated you, calls you names because you fwb with him. This is exactly what this drama portrays and it’s dangerous. Na bi chooses apparently good looking guy who did all the horrible things to her just cause he says he’s changed. Never in a million years people change their true colors. She rejected a guy who loved her since ages just cause of a player.
This sets a wrong precedence to those who learn from dramas about love.

They could have done a better job either at portraying the player or made our love struck fool a little less innocent so we could make sense of the story.