After I'd told my friend about the unintentional anal flashing, he was very excited and had the idea of my going out dressed and equipped similarly but on the metro and "a stranger" (him) touching me, then following me and "taking advantage" somewhere private - something we'd both wanted to do for a while.

We thoroughly planned the time and route, and I wore a very respectable knee-length dress, just without underwear, and that same butt plug. I took the metro as we'd arranged; stood near the door, holding the overhead handles, and waited. It was busy and I had to move several times as it got busier, people were closing in around and I couldn't see through the crowd.

I ended up with strangers pressing and leaning against me, pushing past; then a touch that was a little more than necessary, a little more than appropriate; the feeling of an almost-errection pushing into my back and the barely audible whispered codeword that we'd agreed on.

The duration of the journey, he pawed at my breasts and my ass, he even managed to get his hand under my skirt, teasing the butt plug and my pussy with his fingers, in that crowded metro carriage. Fortunately, it was loud and my gasps could be attributed to the bumps in the momentum.

I got off at the agreed stop, it was getting darker as the evening drew in, headed out of the station towards the park. I looked back, several times, but I couldn't see him. Then I felt a vice-like grip on my wrist as I was pulled into a shadowed sidestreet. He put his hand over my mouth and pushed me against the brick wall (again, codeword), facing away from him, his other hand went to work between my legs, his fingers pumping fast in and out of my dripping cunt until I came, which didn't take long. Then he slapped me on the ass, leaving that stickiness on my skin.

We went for dinner then back to his place.