On a rainy night, they broke up. A water stain remained on the windowsill for three years as she stayed in their old home, nursing old ailments and hiding her deep love between the pages of ancient books. When they meet again after years apart, investment banking executive Shen Yizhen is still distant and cool, but his eyes conceal an anguish he cannot put into words. Burdened by enormous debts and a gravely ill family member, he cruelly pushed away the woman he loved, yet quietly stayed by her side. Their mutual love cannot overcome the shackles of reality. Though they know they still care for each other, they can only let go in pain. The rain on the windowsill will eventually stop, but the regret will haunt them for the rest of their lives. In the end, they love but cannot be together, each going their separate way.
