Sachiko, a wife, lives with her husband who runs a hot spring inn in the countryside. - One day, her son, who lives alone in Tokyo, returns home and spends time with his family for the first time in a while. - That night, the son inadvertently witnesses the couple's nightly activities and is left feeling distressed. - The next day, the son bumps into the open-air bath where his mother is taking a bath, and cannot control his lust and rapes her, but Sachiko feels it even though she resists verbally.