좌측 현재, 우측 미래
-Description
7-year-old Hyun-jae, always accidentally on Mirae's left side and a bit quirky, gives Mirae a toy ring before moving away, making a sincere promise to marry her when he grows up. Thirteen years later, they reunite at the same university but in different departments. As the grownup Hyun-jae once again finds himself on Mirae's left side after a long separation, their journey to fulfill "the promise they made in childhood" begins with twists and turns!