She divorced her husband and raised her son on her own.He goes on a trip to a hot spring with his son, who has become a shut-in due to his troubles with relationships.I don't want to see my child suffering...I want to help him heal somehow.His love for his son turns into a forbidden love.Reika thought that she was just encouraging her son, but was swallowed up by the woman's pleasure.In a small inn deep in the mountains, Reika repeatedly rubs her body and climaxes again and again... A forbidden incest story where they end up wanting each other.