Ryoko, who divorced her husband ten years ago, raised Hiroaki single-handedly. Hiroaki graduated and got a job offer, perhaps because he desperately raised him so as not to make him feel pity. I felt relieved that his child-rearing had settled down, but on the other hand, I felt like I had lost his purpose in life and left a gaping hole in my heart. When he was feeling such loneliness, he was invited to a hot spring trip by Hiroaki. "I want to go on a graduation trip with my mother who let me go to university." Ryoko and Hiroaki set off on a graduation trip alone.
