Prologue: Normalcy

Ariadne (or Ari for her friends) is a quite normal girl in a normal town. She is an eighteen year old girl and was about to start college. She lives in a medium-sized European town, with her little sister and her parents. She has nice red long hair. Her boobs and ass weren't as big as her classmate's and due to them making fun of it she had became quite shy over the years. All in all everything's normal.
But that changed during summer holiday. She was at home during holidays. It didn't bother her much that her family didn't like travelling, now she could go to concerts with her friends. After one concert she arrived home late. Her parents already went to bed and because Ari was bored she decided to turn on the tv. What she saw first was the news. The anchor told her audience that something exciting was going to happen: the Lennon-McCartney comet would pass Earth at a short distance. It would be a spectacular sight that same night. Ari didn't bother. All she knew is: she was tired as hell. So she decided to go to bed. After some minutes tossing she doze off to a good regular sleeping.
What happened the following hours will always be a mystery. If Ari would be awake that night and looked out of the window, she would notice a bright red flash of light that lit up the whole sky. It was just three seconds, but it changed the world forever. After that no car was heard parking. No tv could be heard in any living room. Overflying aircraft would never be seen again.
Ari woke up at 10 o'clock in the morning. She noticed the house was very silent. Too silent. When she went to the living room she didn't see her parents. No note was left. Confused she decided to make breakfast. After eating she called her mom on her phone, but no-one answered. Now really worried she went out to the police station. During her walk she noticed that nobody seemed to be in town except her. The police station off course, was also empty. She started to wonder if she was the last girl on earth now.
When she was almost heard she heard a familiar noise: a dog barking. Inside a house she saw a big black Rottweiler. It was trapped in the house of his former owners and had no food and water. Ari thought it must been starving, so she ran around the house to see if she could get in somehow. All doors were locked so she picked up a brick and smashed it through the window. She went inside the house and the dog walked to her, happy to see someone again. Ari found its bowl and gave him some water. The dog gratefully drank it and while Ari sat on the bench wondering what to do next, the dog came up to her and gave her a thankful lick on her face. She thought 'If he likes me now, he can keep me company so I'm not alone' and took him home. As her now owner, she decided to name him Romulus.
That afternoon she and Romulus formed a bond while playing and walking through the deserted town. He was a playful dog, and very friendly and calm too. After that they ate their dinner. Ari was lucky, because the shops were still full so she could take all the food she needed to survive. She didn't know where everyone else went to but she hoped everyone was ok. In the evening she and Romulus cuddled on the bench. What else could they do? When they both were getting tired Romulus lay down in the corner of the living room and fell asleep. Ari herself went up to her bedroom, took her clothes of and fell asleep too.
Again that night a second red flash could be seen, if there was somebody to see it. This one reshaped the earth. In five seconds, where once large acres were, were now forests. Overfished oceans were full of life again. New strange species were created, like God decided to run Genesis 2.0. And it changed Ari and Romulus too.
When Ari woke up she was a bit dizzy. She felt ... different. Somehow she didn't worry about her former family, instead she was eager to explore the earth now she was limited of her former boundaries: family, school, expectations... 'How strange, ' she thought, the clothes she wore yesterday weren't there anymore. Ow well, I just take a look in the closet then. But no clothes there either. Feeling a bit ashamed she went downstairs. There was no-one to look at her, so what the heck.
She immediately saw the interior of the room had changed. TV and radio, and all electronics, were gone. Romulus greeted her with a bark. Not feeling hungry at all, like she would never be again, she sat down on the bench in the living room. What would she dow now, in this strange world? Ari decided that she would do what she always wanted: to travel around the world! So she and Romulus left the house. Without packing (there was nothing to pack), nude, and just the two of them.
Ari noticed that the pavers in town were gone too. Now the streets were covered with soft grass, which she found very comfortable. Ari and Romulus decided to take a last walk around town before setting off to the big world.
After a while again a bark could be heard. A Labrador was walking the streets. It was a female, and Romulus noticed that too. He walked up to the female and smelled her ass. How lucky, she was in heat! Romulus became very excited and Ari could see the tip of his dick coming out of his sheath. She wasn't grossed out by this, or shocked, no she found it quite ... exciting. The female lab presented herself to Romulus and he put his paws around the lab. His now completely erect penis, which Ari could see measured 11 inches, quickly disappeared in the female. Romulus started to hammer her like a turbine. Ari started to feel a feeling in her belly ... she started to feel horny! She was never into boys, or girls, but seeing this strange scene in front of her made her pussy very wet. She started to wonder how that big dick would feel inside of her, instead of that lab bitch.
She laid down in the grass and slowly started to finger herself, never losing sight of Romulus. He had already knotted the bitch and while Ari was masturbating she could see Romulus pull himself free from the female dog. Out of her pussy came his still erect penis, those astonishing 11 inches. And a lot of cum too! Seeing that drove Ari over the edge and she came very hard. The lab quickly run away, not in for another round.
A few minutes later Ari and Romulus went as well and set off to the forest near their hometown. Romulus noticed a strange smell. It was a bit like a bitch in heat, but there were no dogs around anymore. Thinking of the wonderful experience he just had, he started to get horny again. If he only knew where that smell came from! Ari noticed Romulus getting a bit frisky and stopped walking to see what was going on.
So she sat down near a tree and called Romulus over. Now she could see the pink tip of Romulus' penis extending from his sheath again! She became wet again. Romulus noticed this too, the smell he hat noticed earlier was getting more intense and he now located the source: it was Ari her pussy juice. Was she a bitch too then, he wondered. That would mean he could fuck whenever he wanted!
Now even more horny he decided to check things out and to Ari's surprise he dove his tongue straight into her pussy. She didn't freak out, rather it felt to her like it was very normal. Romulus quickly lapped up her juices and found out she was as horny as he was. So he kept licking. It drove Ari wild!
"Oh Romulus good boy LICK MEEEEE!"
And boy he did. He licked her clit and deep in her pussy. Ari loved it. And in a sudden she gave a loud scream and came HARD. A powerful orgasm hit her. Her pussy went very wet again and Romulus licked those juices up as well, causing a second orgasm.
After she came again she rolled over and went down on her knees, ready to stand up and walk further. But while she came, Romulus didn't and he desperately wanted to. So he put is front paws on Ari's shoulders, and with that extra weight she had to go on all fours if she didn't want to smack her face to the ground. This left her ass high up in the air.
Now Romulus had her where he wanted her. He positioned him behind her and with one mighty thrust he drove his dick right in Ari's still wet pussy. It was heaven! For Ari this happened in less than ten seconds and while she still had to figure out what actually happened, all she knew is that a big dog dick was hammering her pussy and it felt very good. She felt Romulus hitting spots she didn't even know they existed! Romulus thrusted as hard as he could because he wanted to breed Ari as good as he could do. He just loved the feeling of soft human flesh around his dick. Ari let out another scream and experienced her fourth orgasm that day.
Suddenly she felt something very big entering her pussy. She quickly realized it was Romulus' knot. He started thrusting very fast, and then held still. Then Ari could feel gallons of dog cum invading her pussy. The thought alone made her cum again. After the last drip she and Romulus were locked for about twenty minutes and then Romulus could pull out. Also out came his own cum which left a cum pool under Ari.
Romulus started licking Ari cleand, lapping up a mixture of her and his juices. He did it so well that Ari didn't even feel the need to clean up. Somehow she liked it, being literally a dirty girl. Exhausted by the fucking she hugged Romulus and they rested a bit.
The evening fell. Since Ari didn't bring anything with her she decided to sleep on an open spot in the forest. She was still tired from fucking so she quickly fell asleep. In her sleep she spread her legs which would give any passengers a wonderful view of her pussy. They would see a tight pussy with a little red bush. And a very interested big black dog!
Romulus himself was very horny again but he understood Ari wasn't available now. So he decided to take things in his own hands. He licked Ari's pussy until he thought it was wet enough to fuck it again. His cock became hard and he stepped over Ari's body with his front paws next to her breasts.
Now he moved into Ari's body and started pumping in a calm rhythm. He just loved the feeling of pussy around his cock. He began to increase the rhythm and saw Ari's small body shaking slightly now. He particularly noted her small breasts bouncing and that sight drove him crazy. He now knew what he wanted. When he fell his orgasm coming, he pulled out and pressed his penis between her breasts. A few strokes more and then he came all over her breats, stomach and pussy. He gently cleaned her body and satisfied, he dozed off to sleep.