Kaho Mochida lost her beloved only son, Shun, and as a result divorced her husband. Even after five years her wound has not healed and continues to torment her. One day, at a new job she is dispatched to, she reunites with her high school friend Takahashi Fumiya. Like Kaho, he is divorced and has a son, Ryota, who is the same age as the deceased Shun. Such coincidences happen... or she thought so, but when Fumiya brought Ryota home, his smile and mannerisms were exactly like Shun's...