It was one of those rare days where I had the entire house to myself, Dad was out at golf, and Mom had to take my younger twin brothers, Jake and James, to their soccer semi-finals, which meant that she would have to stay and watch. It also meant that I had the best part of two hours to do whatever I wanted.

I should probably introduce myself, Cassidy, 17 and drop dead gorgeous, with short, slightly wavy brown hair, blue eyes, and, if I do say so myself, a graceful neck leading to a more than adequate c cup that really accentuated my face, when guys bothered to raise their eyes. Oh and did I mention I was modest as well.
Guys. That was the current problem. If I had a boyfriend we would probably already be bouncing around on my bed. I had had a few, but the first two were terrible in bed, and pretty damn small too. And I dumped them after about a month of putting up with their excuses. The third one, Rick, was absolutely great in bed, at least seven or eight inches long, and he knew how to use it. He looked great with me too. Until I found out that the bastard was sleeping around at a party we went to.

That was three weeks ago, and I had dropped him like a rock, making sure he sank. But the results of that decision were coming home to roost, three weeks without getting laid, three weeks with only my fingers to cool me off, and that was only when I knew I could get away with it, when I knew that mom or Dad or one of the twins wasn’t going to burst into my room to tell me about chores or take our Dalmatian, Billy for a walk, or something else I didn’t care about. I mean seriously, who cares about who got what colour penalty in whatever macho sport they were watching? Just more proof that all guys have balls for brains, the number of them it takes to follow one around a field for an hour, not to mention the people who are more than happy to sit back and watch!

But that didn’t solve any of my problems, and thinking about Rick’s eight inches was almost making me drool, and other parts of my body were starting to follow suit. I sat down on the sofa in front of the telly and picked up the remote, I wanted this orgasm to wait, and it took all my self control not to rip off my top and my jean shorts and finger myself to nirvana.

I had recorded one of those late night semi-porno movies, and I watched it for about 45 minutes, my horniness slowly giving way to frustration as I forbade myself from touching my ‘hot spot’. And then our dog Billy came in, he was probably just hungry and he nudged me. Right between the legs. I moaned in shock and pleasure as his bump crushed my clit against the seam of my pants, almost making me come instantly. Before I could push him away, he did it again, again rubbing the seam of my pants hard against my drippy pussy. I shuddered, and pulled him away, telling him I would deal with him soon. I sent him over to the corner, so that I could ‘deal with’ myself first.
I ripped of my shorts and pulled my top down to reveal my tits, I had prepared well, I didn’t have any underwear to get in the way as I slammed two fingers into my sopping pussy, the knowledge that my dog was watching everything I was doing with a rather quizzical eye making everything more… dirty. I groaned as my body jerked and my pussy tightened around the fingers that gave it the release I had denied it.
I relaxed against the couch, panting, it definitely had been worthwhile holding out, I looked for the tv remote, it had been knocked under the sofa while I was ‘busy’. I knelt down to reach for it, giggling, and spoke out loud
“Figures that my best orgasm in three weeks is me finger-fucking myself in front of Billy, I really am fucked up.”

All of a sudden a weight crashed down on top of me, a big, heavy, furry weight. To this day, I don’t know whether it was me saying “Billy…up” or whether he was just horny from my scent, but that was the situation I ended up in, on all fours, with my pet Dalmatian trying to mount me. I had a few seconds of frenzied panic, as his cock searched for my entrance, and then he rammed it home, spearing my sensitive flesh and bumping me forwards so hard that I knocked my head against the side of the sofa.

I couldn’t think, all I could do was feel the painful heat of Billy’s thick hard cock as it filled me. Oh god did it fill me, he was easily as big as Rick, and definitely thicker, the little voice saying this was wrong was getting smaller and smaller as I lost myself to the feel of fullness.
And then he started pumping.

No slow build up, oh no, straight into fifth gear, ramming into me as fast as he could, I grabbed the leg of the sofa and hung on for dear life, as his pistoning jerked me back and forth on the floor, the pain of intrusion slowly disappearing into a wave of pure pleasure that crashed onto my again and again and again, and sent me Cumming in a frenzy. I didn’t care if it was a dog, or if it was wrong, because damn did it feel right.
Billy kept ramming me, harder and faster than Rick ever did, and he had already lasted twice again as long as Rick, turning me into a ball of mewling, shuddering, incoherent, pleasure. And then the end of his cock started getting thicker, swelling as he thrust back and forth inside me, and finally the entire lump, I’d heard it being called a knot, forced its way into my tight kitty, sealing me as his as he started pouring his boiling hot cum inside me. He was still jerking back and forth and thrust one more time to ensure he was solidly inside me, the action swinging his heavy ball sack forward and under, until it slapped hard against my clit, sending me off for one final time as my pussy started leaking his hot doggy cum down my legs.

Then I had to grab harder at the sofa, as he turned around, and decided he wanted to go back the corner I had sent him. I yelled out “stay” and thankfully he stopped, his knot still embedded inside me. We stayed like that for a good fifteen minutes, him standing still, me on my knees, arms wrapped around the sofa leg, joined by his pulsating cock, until with a loud ‘POP’, he finally slid out of me, allowing the rest of our juices to cascade down my legs as I nearly collapsed. I slowly pushed my way up the sofa until I was standing, albeit on very shaky legs, then turned and looked around the room, at the mess of cum at my feet, thank go the floor was tiled, it might have nearly killed my knees but at least cleaning up would be easy, at the clock that said I had fifteen minutes before I could expect somebody home, at the mirror that showed a hot young girl that looked like she had been royally fucked, hair in a mess, covered in sweat, tits still hanging out of a sweaty pink shirt, and cum still leaking from between red pussy lips, and then finally I looked over at Billy, who was sitting in his corner and licking himself.

“Bad dog” I whispered, running my hand down to stop the flow of his juices from my abused kitty.

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