I was out walking my dog on our usual route, and he heard something first then I did as well. It sounded like a woman screaming, but I couldn’t make it out so we continued along our way and got closer to the sound. As I approached a children’s playground, I looked over, and saw a woman ~20F sitting up, legs spread apart, pants at her right ankle, getting her neck kissed while being fingered. She was going mental, loving every second of it moaning very loudly, and I couldn’t help but stop as I couldn’t believe my eyes. Moments after I stopped she erupted, screaming and shaking having what seemed like an incredible orgasm. They didn’t see me, but it was damn hot to witness!