Yuki's parents divorced 17 years ago, and Yuki followed his father. - After graduating from university, he decided to meet his mother Reiko for the first time in a while to report on his employment. - Reiko wanted to go on a trip with mother and son without having to bathe in the water, so she booked a hot spring inn deep in the mountains. - Reiko was itching to see her son again after a long time.