ランダムな男の黒いspeedoでオナニーして絶頂

I was at my local aquatic centre and went into a shower cubicle after a spa session. A guy who showered before me had left his black speedo hanging up inside the cubicle. Curious if it would fit me, I picked it up to inspect it and check the size. It was one size larger than me and still a little wet from being used. The thought of putting it on after another guys cock and balls had been in it made me rock hard. Watch the video to see what happened next.