Hokkaido, the coldest island in Japan. A 35‑year‑old woman is a bird scientist. As a child, she was abandoned by her mother and ended up with foster parents. The seven‑year‑old girl’s father died, and her mother’s new boyfriend is bullying her. And the mother herself doesn’t want to be left alone, so she puts up with all of this. One day, the fates of these two people become intertwined in a tight knot.