Years later, I learn my sister heard me jerking off through my teen years.
A couple of years back, my sister and I were visiting when we decided to go to a bar and get a bite to eat. On the way home, she asked how my sex life was (it's always been a subject). I told her it's been ok. She said 'Ok as in your getting some pussy or ok since you can jack off'. I didn't answer. She said, 'Oh come on, your a guy you jack off a lot. I heard you all the time when I lived at home. Hell, I've watched you do it over 30 times.' I told her she was lying.
She then began to tell me of how I would wake up in the morning and jack off, get home from school and jack off twice, jack off once before supper and twice at bedtime. She then told me how I inspired her to masturbate more also. She asked me if I still did it. I laughed and said yes. I later confessed to still doing it twice or more per day. She said she used to have a tablet where she and her friends recorded when they heard me jacking off. I then really thought she was lying. Then she told me about a slumber party she had and how they sat in the tree next to my window watching me jerk off. She said she and my mother used to laugh at how many paper towels I went through in a week and how they 'knew what I was doing'.
We later sat down and figured out that since I was 12, I have jerked off nearly 30,000 times and at 1 oz per cum shot, it would fill 1,875 16 oz soda bottles. Now that's a lot of cum!