Aiko, a mother who is sexually frustrated because her husband is away on a business trip, masturbates out of loneliness. Her son Masato becomes excited when he sees Aiko masturbating and squirting, and approaches his mother and caresses her passionately. Aiko resists, but the pleasure she hasn't felt in a long time makes her cum and squirt. Masato then thrusts his rock hard cock in front of Aiko...