The Only Difference is the 'S'

Maybe I'd been too engrossed to notice things either, because I suddenly became aware that Sam's fingertip had strayed down from my scrotum, across my perineum and was now knocking gently on my back door, while all the time her mouth engulfed my cock and her palm kneaded my balls. It was a peculiar sensation to feel a woman's fingertip exploring my anus, wriggling gently as it tried to find the entrance, and if truth be told, it was an oddly erotic sensation as well. Erotic enough for me not to want to stop it and in fact I even tried to spread my legs a little further to show my assent.

By now, of course, I'd got two of my fingers exploring the top of the cleft between her buttocks and so, by leaning a bit to one side, I found I was able to reach further down until my fingertip just, and I do mean just, found her own rosebud and I was also probing the tradesman's entrance. Now we were both probing each other's bottoms, with very little success it must be said, as neither of us had any lubricant, but it was nevertheless a novel and exciting activity. Once again and to my surprise she had raised no objection and I revelled in the new sensations of investigating her cleft. It did seem a bit strange that a woman who wouldn't let me feel her tits would let me prod her bum-hole, but who was I to argue.
Then I felt her fingers move away to rest briefly around the shaft of my cock as she took it deeper into her mouth for a couple of strokes, before returning to my arse. My immediate thought was that she needed to change the position of her mouth on my shaft, but then I felt the wetness of her fingertip slipping into my anus through the security of my sphincter, and then I realised that she had merely gone to collect saliva for use as a lubricant.

I'd never had a finger in my rectum before, in fact I'd always considered my arse to be strictly no entry, but the feeling was extremely stimulating and highly erotic. The feel of her finger sliding in and out of my hole combined with her mouth pumping up and down my cock was having its effect, and that marvellous sensation of cum collecting like a geyser about to erupt was already starting. I hate to admit it, but I loved that finger in my arse.