Chapter 1: The Morning on the Building Site

It was the start of what turned out to be a very exciting day when we took the dog for a walk in the morning and had a long drawn-out dirty session in the middle of a big building site, with lots of sucking, fingering, licking and object penetration. I was fucking Abi while she was kneeling naked in a wheelbarrow in someone’s new front room. I had attached some clothes pegs to Abi’s little nipples, each tied to a string with a large bolt tied on the end. The bolts were dangling outside the wheelbarrow, stretching Abi’s little tits, and making her whimper in pleasure and pain.

Abi was very excited and almost shouting “Fuck me brother, fuck your dirty little incestuous sister and fill her vagina up with your lovely brotherly sperm!”. I had to slap her bottom and tell her to be quiet, as those words didn’t allow for much misinterpretation by any unsuspecting passer-by, she giggled and then reduced the level of her voice to a loud conversational level, but she kept looking back at me and telling me that she was a very dirty schoolgirl who just loved under-aged incestuous sex, having her brother’s penis in her mouth, that she loved me to shove all sorts of perverted objects into her dirty vagina, and particularly that she liked my penis up her cunt (a word she rarely used at that time), then as she was saying all of this she arched her back and reached behind herself to spread her bum cheeks apart, revealing her anus.

“I’ve been looking at some of those photographs in Dad’s dirty porn collection, where a man is sticking his penis or a vibrator up a girl’s bum, and I’ve had some very dirty dreams over the past few nights where you’ve been doing those sort of things to me brother!” Abi said. “Oh, have you?” I replied, “and what do you think about anal sex Abi?”.

“I think that it is very perverted brother!”. I nodded and agreed that it was very dirty. She looked back at me and said “Thinking about those pictures and what those dirty men are doing to those girls’ bums, is making me feel very naughty right now, and I really want to know how it feels to have something pushed into my anus, so can we try it? Would that be OK with you?”. I nodded again, and she continued “Just to start with, why don’t you spit on your finger and rub my bum with the spit and then see if you can finger fuck your sister’s anus while you’re fucking her vagina?”.

Phew, that sounded like a very nicely dirty thing to do, so I did just as she asked, and for the first time I felt the thrill of inserting my finger into a girls rectum. Abi shuddered, moaned and gasped as my fingertip penetrated her most intimate part. At first I could only get the tip of my finger in, as it was so tight, but I pulled it back out and dribbled some more spit onto it, and onto Abi’s tight little hole, then I tried again. Abi’s tight little anus still resisted, but suddenly my middle finger went all the way in, and Abi nearly exploded, gasping and shuddering as she had a huge orgasm. All of this was too much for me and I shot my incestuous sperm deep into my teenage sister’s body too.

I had thrown my head back as my orgasm hit, and had then nearly fallen to my knees with the intensity of it, but as we both recovered Abi said, “Wow, that was awesome! Having your finger up my bum felt so dirty and perverted and having your lovely brother’s penis deep in my vagina in this position is just bliss”. She smiled back at me and said “And how was it for you?” I grinned back and said “Yep, awesome just about sums it up!”. She then said with wide open eyes, “Did you like pushing your finger into your little sister’s dirty bottom?”. “Oh yes”, I said, “we can do that again”, then I bent down and dribbled some more spit onto the finger embedded in Abi’s anus, before starting to finger fuck it some more.

Abi shuddered again and her chest flopped down into the barrow and one of the pegs flicked off, leaving only one of her little titties being stretched, “Oh, please keep doing that while you fuck the dirty spunk which you’ve just spurted into my incestuous vagina some more”, she said. So I did just that, and we both felt wonderfully dirty and perverted and joined by our under-aged family sexual connection, particularly as we’d just found another new dimension to it.