
YN and Nayeon were classmates back in high school. Two different personalities, Nayeon is a bully who orders YN for her own benefit through his attribute of having an exceptional intelligence and social awkwardness with people. 15 years later, they met again unexpectedly, got introduced to their improvements over their lives. As they try to move forward from their horrible past, a turn of events pushes them to revisit and realize their regrets.

It follows the story of YN as he goes through the challenges he has to face from the consequences of being the center of their decisions driven by their respective desires of claiming him, in contradiction to the thought that his life would only change for the better after being Mina's lucky boyfriend and getting introduced to the rest of the members.