Repeated wet dreams.
Sayuri Moronaga, has been having nightly dreams. Dreams with such immoral content that when she wakes up in the morning she finds her underwear soiled...
She was glad they were just dreams.
The person she's with in these dreams is her son Yuhei.
Sayuri, who has been estranged from sexual matters for a long time because her husband Masaki is sent to work abroad, feels ashamed of herself for feeling so much frustration. And at the same time, even though they are dreams, the person in them is her own child. She wonders if she really has such desires.
Then one day... things take an unexpected turn...