First time - what a surprise

Condom first". These were the days of super safe sex, so of course that was absolutely the done thing (like when she went down on me). She slid on a rubber and then sat back, as for the first time in my life I began to give head. I started with the usual places that I like to be licked and sucked on and this was obviously the right thing to be doing, as she moaned her approval. I couldn't believe my luck. Totally at random I picked this corner of Amsterdam and had picked this lady out of all of the windows nearby. I got a bit over excited and nearly gagged myself a couple of times, which she loved.
Again she gently pushed me back and leaned in close to whisper. This time she said "would you like me to fuck you?"
"Yes" was my sub second response. Then 2 seconds later I said "But i've never done... this.. " pointing at her cock ".. before. so please be gentle?" She laughed out loud this time. "Of course I will""
She positioned some cushions and asked me to lay on them. As I lay back she lifted my left into the air and propped some more cushions under my ass, to give me more 'lift'.
Then cam the moment of thruth. She started to rub the end of her cock against my pliable, yet virgin ass hole. She rubbed in some lube, positioned herself again and said "Ready?". "Oh yes. Please fuck my ass". She smiled and started to push herself into me. The feeling was sublime. she started to withdraw after only an inch and then pushed in again, slightly deeper. Then back out again and deeper still. This carried on until she was balls deep in my ass. My head was back while I was taking in all that had happened and was now happening. slowly but surely she started to fuck me. My legs in the air, me holding them behind my knees, and her kneeling in front of me sliding her cock in and out of my ass hole. I was in heaven. The pumping got progressively harder and slightly quicker. I was being fucked.