What does Norebang/music represent?

Norebang/music symbolizes the utter expression of emotion, and by extension, love. While out singing norebang, Daniel and Natasha end up kissing as their emotions are on clear display through the music. This thrills Daniel, who realizes in that moment that what he has with Natasha is real love, not mere science or a chemical reaction. It is a transformative moment that changes everything.