Miyuki, the mother, is more erotic than anyone else. That's when her son noticed it, some time after his father left home on a solo assignment. Miyuki, who had fallen into frustration, was so absorbed in masturbation that she didn't even notice she was being watched by her son. Her figure is too erotic... A son who seeks his mother, knowing it's a forbidden relationship, and a mother who can't refuse. The two who have crossed the line seek each other to the extreme.