Seung-joon and Yoo-jin have a long history, having been friends since childhood and even having had their first romantic experience with each other. Despite this, Seung-joon has always been just a friend to Yoo-jin. As she confides in him about her heartbreak, Seung-joon realizes that he has feelings for her and decides to confess his love.
Feeling guilty about his mistake with Da-yeon, Jung-soo decides to visit Yoo-jin to apologize and make things right. When they see each other again, they both realize that their feelings for each other never faded away, and they start to rekindle their relationship.
At the same time, Seung-joon must confront his feelings for Yoo-jin and decide whether to pursue a romantic relationship with her or respect her relationship with Jung-soo. As they all navigate the complexities of love and relationships, they come to understand the true meaning of friendship and the importance of being honest with themselves and others.