Watching A Guy Pleasure Himself With My Panties

I have caught the neighbor guy taking my panties off the clothes line. I put some out the next day late in the evening. I hid on my deck and saw him take them. I followed him to his garage and hid behind some bushes where I saw him slip them on and rub himself in them before pulling the waist band back and shooting his cum. I was so turned on watching this, I wanted to jump out and surprise him and help him get off with my panties but I knew I should just watch and enjoy and not ruin the fun he was having by scaring him.