I used to have a neighbor at the rear of my property who had an above ground swimming pool with an elevated deck, maybe 75 feet away. The mom and young daughter were very hot and I used to sit at my desk and watch them lay out in the sun and jack off.
One day the daughter (I believe she was 18 or 19) was laying out and she loosened teh straps of her top to reveal some very nice perky tits. I raised the blinds and stood at the window stroking. I noticed a few time she would look my way and show more of her tits. She pushed her bottoms down about mid-cheek and I started stroking like mad and shot my cum against the window as she was looking my way. She got up slowly showing her full tits to me and slowly pulled her bottoms up as she went into the house.
Just to see if she was indeed watching me, the next day I kept the blinds down when she came out, she proceeded to take her top off and lie on her back. She then rolled her bottoms down and started fingering her pussy. I then raised the blinds again and stood at the window and stroked for her and it appeared we both came at the same time.
This continued for the rest of the summer until she went away to college. Her family moved away soon after that so, the good times ended but, it was great fun while it lasted.