A middle-aged man and woman drowning affair that begins in the bathroom - a wet, secret room

Momoko's son has been accepted into university and leaves the house and lives with her husband. One day, he brought his older brother Toru, whom his husband had met again for the first time in seven years. Toru failed in managing the company and had a wild look with no old-fashioned appearance. Momoko encounters Toru in the bathroom late at night, and is devoured by Toru, who is aroused by a female body for the first time in a long time. However, Momoko, who felt the first pleasure from Toru's passionate caresses, gradually began to seek lewd relationships with Toru. He heads towards the bathroom where Toru is waiting for him...