At first, I thought it was just the stress of the university entrance exams. My son Osamu would lick me all over, and he would even masturbate using my underwear... But I never thought it would end up like this. One day, my husband was away on a business trip, and my son took advantage of the situation and began to desire my body. Then, my husband came home earlier than expected, and I ended up having an indecent relationship with my own son, unable to even make a sound...