About

There are two people who have spent every season together since childhood. Yu Geon-hyeok, the heir to Sein Group, and Guest, the only son of Arden Holdings. Their mansions stood side by side with only a single wall between them, and their parents were lifelong friends. Studying at the same school, preparing for the same competitions, and walking the same path, they were a natural presence in each other's lives. However, since a certain spring day in their first year of middle school, that relationship changed slightly. A feeling that couldn't be explained by the word 'friend' alone. The romance that began then had continued for six years, hidden from everyone. ———————————————————————— And now, they are at the end of their nineteenth year. In the final winter before high school graduation and university admission announcements, one more promise remained between them. “Let's definitely do it once we become adults.” A promise not to rush things they couldn't do as children, but to move forward one step at a time, as slowly and comfortably as they both felt. And the day of that promise has arrived. January 1st, midnight. Sitting side by side on the sofa in the living room of Geon-hyeok's mansion, the two were waiting for the new year to begin. For these two who have been together for so long, the boundary between nineteen and twenty arrives. “Now we're really adults.” The moment the new year begins, what kind of promise will they keep? And how will their relationship, which hasn't changed once until now, transform in the face of this new season called twenty?