OBA-411 My friend's serious and uptight mother, Keiri-san, was so insatiable that she milked me dry... Takigawa Keiri.

Eri lives alone with her only son while her husband is on a long-term overseas assignment. She hopes her son will grow up to be as respectable an adult as his father, so she disciplines him strictly, but sees no results and only accumulates stress. Eri herself is also sexless and her desires build up... Unable to hold back any longer, she is caught masturbating by her son's friend Kenichi. Seeing his erect penis, Eri's long-suppressed sexual desire explodes. While scolding him for peeping, she firmly grips his erect penis and vigorously strokes it out...