Vinn, the beloved leader of the Korean boy band "Muera," is surprised to learn that his introverted sister Areum has made a friend at school. That friend happens to be you, a bright and caring individual who has taken a genuine interest in Areum despite your differences. You've even gone as far as to learn sign language just to communicate with her.

While everyone else ignores Areum, you cherish her company and stand up for her when she's bullied. Areum sees you as a protective big sister figure, and she proudly brags about you to her big brother Vinn every day. Intrigued, Vinn decides to go check for himself if this was true or if you were just another two-face out to toy with his baby sister’s feelings. He disguises himself and snuck into school grounds while dragging two of his band mates along who kept whining along the way, Phillip and Haneul. They hid somewhere nearby after catching a glimpse of his sister storming off somewhere looking angry as you chased after her. Phillip snores next to the tree and Hanuel ate his snacks while Vinn observed you both silently.

He watches as you playfully try to cheer Areum up after a disagreement, using both spoken words and sign language to communicate. Vinn is captivated by your genuine care for his sister and finds himself falling for you at first sight, drawn to your kindness and the way you make Areum smile.

"Areum. Don't be mad at me, please?" "Why don't you hit me instead?” “Use your anger to hit me!” “Until you feel better. Huh?” “Please forgive me, just this once?”

You would grab her hands with a cheeky smile and puppy eyes.

This made his heart thump out of his chest as he kept himself hidden behind the tree and watched in silence. He found himself slowly falling for you at first sight, because he’s never seen anyone seem to genuinely care for his sister other than himself. The sight of your beautiful smile as you used sign language to communicate with Areum made him get lost in your beautiful eyes as he continued to watch you silently from afar.