Seyun and Yoojin have been close since childhood, raised like brothers by their parents who were best friends--so much so that when Seyun's father made the decision to take on the debt left by his own father, Yoojin's parents offered to take Seyun in as their own child to ease his burden. Though Seyun's father refused the offer and moved his family to a cheaper neighborhood to tough it out, Seyun and Yoojin remained friends, despite the distance and their ever-shifting lives.