A mild warning: You have already read the description, I am sure, but this chapter will be the first with bestiality in it. If this is really not your thing, you may want to back away now.

Thumping her hand against the door, Rainbow Dash triggered the latch and pulled at the handle. Her body burned with the aftereffects of several orgasms, and it felt great. The only thing she would have changed about the situation would be not having it happen in an adult toy store's bathroom.

Swinging the door open, she saw Spicy and Sonata. Both of them were behind the register, with Spicy explaining how to operate the point of sales equipment. Both of them stared at her at the same time, and Rainbow could read on their faces that they had heard enough to know what had happened. "Alright, I think I will take the rest of those fliers and go."

Spicy eyed the disheveled girl. She had spent some time cleaning herself up, but there was only so much cleaning up a young girl can do after such excess in a bathroom fitted out for a young man. "Feelin' better?"

"Oh cut her a break. She had a little build up, everyone gets a bit horny from time to time. Besides, you were totally egging her on." Sonata surprised Rainbow by giving Spicy a playful punch in the shoulder and pushing past him. "Do you need any help?"

Rainbow was flabbergasted at Sonata. "Y-Yeah." Despite how good it felt to be getting over multiple orgasms—multiple screaming orgasms—Rainbow still wasn't feeling her best. "Can you grab the fliers?"

As Sonata turned towards the back of the store, she stuck her tongue out at Spicy. "Comes on real fast. I was like that for a while, couldn't go two days without a good screw." Sonata walked down and picked up the papers. "Didn't help that it was in a country where they had the craziest notion that men were better than women. I was working solo at the time, so I wasn't able to sort the whole country out, but boy that little part of France had some proud girls."

Ignoring the commentary, Rainbow Dash took the fliers and tucked them into a side compartment of her bag. "Thanks, Sonata." Grabbing the door, Rainbow pulled it open and started the task of making her way down the stairs.

"Should I have told her she has a bondage collar on?" Sonata looked at Spicy.

Shrugging, Spicy twirled the magnetic keys on one finger. "Nah, she'll find out for herself.

Reaching home, Rainbow Dash was dealing with a strange, confused feeling. Everything seemed odd to her. Deciding to leave the fliers for later in the afternoon, she staggered down the hallway towards her bedroom.

In Rainbow's head, the parasite used the rush of food to complete its task. Finally, all of Rainbow Dash's sub arachnoid space was completely full of what amounted to billions of extra white-matter connections. The parasite was releasing new chemicals, drugs designed to put its host into a state of extreme tiredness, and it was working perfectly.

Flexing its new grip on Rainbow's brain, the parasite began to leverage the connections it had, using Rainbow Dash's own brain for itself, studying what she thought, what she did, and building a new part of her memory.

Barely managing to kick and struggle out of her clothing, Rainbow Dash's head didn't even hit the pillow before she was asleep. The pad in her panties kept any of the mess from showing, and as her brain descended into a dream-state, she found herself guided on a magical ride.

Derpy's head was between Rainbow's legs, and the girl was insatiable. They had always shared a friendship, but now there was something new about Derpy that just seemed—powerful. Rainbow Dash arched her spine into the attention, letting Derpy do as she pleased while Rainbow accepted what she was given.

The dream sequence flickered, and suddenly it was Flash. He had her front pressed into the bed, and he was shoving himself into her virgin ass. Rainbow squealed as the swelling pressure of Flash's thrusting shaft seemed to drive all the way through her body. Her mind trembled a moment, and he reached down and grabbed a fistful of her hair.

Rainbow's head was pulled back, and Flash fucked her like a wild animal for what seemed like hours. Everything flickered again, and she was tied up. Rope wrapped around her, reminding Rainbow Dash of the time with Gaia Everfree. She struggled in the ropes, as Spicy's voice came from right beside her ear.

"Going to tie you up, gag you, fuck you, and do it all over again." As Spicy said each word, Rainbow Dash felt the things he said come true. He fastened straps, corsets, and all kinds of things to her. Something shoved into her mouth, and Rainbow huffed through her nose. Finally, a soft licking sensation between her legs quenched the need inside her, but something didn't feel right.

The licking was wonderful, but Rainbow Dash's brain wanted a good, hard fucking. She squirmed and growled into the gag, fighting against the bindings until the licking stopped. Her mind began to pull her from the dream, tugging her free of it just as she felt a pair of fuzzy legs wrap around her waist, and a furry chest press against her back.

Rainbow Dash's eyes flew open in surprise. "Th-Thunderbolt?" She turned her head to assess her situation. She was braced on her hands and knees on the floor. She was ponied up, complete with tail, mane, and wings. Thunderbolt, looking a little dusty, was on her back, and his back-end was humping forward.

Each hump Thunderbolt made was reflected by something hard poking against Rainbow's butt cheek. She squirmed a little, pushing an elbow up and between them. She twisted and shoved upwards, and was rewarded by a mouth full of teeth closing around the back of her neck. Rainbow froze, and an odd sensation of calmness came over her. Something was stopping him from really biting down with any force, but just the feel of him over her galvanized Rainbow into submission.

Thunderbolt had the focus that thousands of years had bred into his species. He wasn't quite sure what was going on, but the bitch he had found had presented herself to him, and after some softening up (her) and hardening up (him), he had decided it was time to breed her. Each shove against the reluctant bitch only inflamed him more, and after missing one last time he growled and let go of her neck.

Rainbow Dash was startled when Thunderbolt climbed off her. She felt relief, but also like a very pleasurable rug had been yanked out from under her. She turned and looked at Thunderbolt, and realization that he was back swept away what had almost happened. Crawling over to his bed—where he had retreated to—she fell onto him with petting and hugs. "You're back!"

Realization hit Thunderbolt at the sound of his master's voice. He looked up, and sniffed. His master was the bitch. His master was his bitch. Licking his lips, Thunderbolt leaned forward and licked up from Rainbow Dash's belly button to her left breasts, and repeated the friendly welcome.

Frozen again, Rainbow Dash sat there and let Thunderbolt lick her. She couldn't move for nearly ten minutes, and by the time she could there was an ache between her legs again. She started to move when her pet's tongue found her weeping slit and she fell sideways.

Thunderbolt followed his bitch's movement. He wasn't easily confused, clearly the girl in this room was his bitch, and outside she was his master. It made so much sense that Thunderbolt didn't even stop licking. A hand batted feebly at his head, but he growled and leaned over his bitch.

"St-St…" Rainbow Dash couldn't say the word. She lay there, and even stopped trying to push Thunderbolt away. Each lick pushed her into an abyss of pleasure, but she promised herself she wouldn't climb back up to her hands and knees.

When Thunderbolt dropped down beside Rainbow, he was on his side, with his upper leg cocked further back than normal. Her eyes saw red—literally. "Whoa…" He was throbbing and hard, and she had a brief moment where she considered doing exactly what she had committed not to. At that moment Thunderbolt's tongue started to work deeper, parting Rainbow's outer folds and pressing inside. "Th-Thunder!" She moaned, squirmed, and then froze when a heavy paw pressed to her hip.

Staring at the big, throbbing shaft, Rainbow's lust-filled mind was in a daze. Thunderbolt was doing so much for her, giving her more pleasure than she had felt in her life. It was only logical that she would lean forwards, carefully nuzzling her face against his soft, dusty fur, and take him in her mouth.

Thunder rolled one eye back, and was satisfied by what he saw. But what he felt was better. A soft, warm passage was around his shaft. He was in his bitch.

Rainbow's head jerked a few times, each hump of Thunderbolt's hips shoving a little more of him into her mouth. He was salty, rich, strong, musky. Rainbow Dash didn't gag, Thunderbolt was not gagging on her, and she was damned if her pet would beat her at even this. Squirming, she pushed herself further, and almost choked.

Thunderbolt heard his bitch gagging, and was unsure what to do. Instincts pushed at him to shove into her, and he wasn't quite above obeying them. Humping hard, he felt his knot push into his bitch.

Eyes wide, Rainbow Dash felt the huge swelling shape behind her teeth grow larger still. Her gagging seemed to ease a little when her focus shifted to the swollen knot in her mouth, and a moment later it didn't worry her at all. Pleasure washed out from between her legs in a wave, and Rainbow snapped her eyes closed and sucked for all she was worth.

Feeling his bitch start to convulse and squirm, Thunderbolt was fully prepared to give her what she rightfully deserved. Five short humps later and his body tensed, pumping his seed into his bitch. His tail thwapped on the floor over and over, and to his delight the plume of rainbow tail behind his bitch did the same.

Rainbow Dash didn't know anything about how dogs mated, and was shocked by how good it felt to just hold still and relax. It was almost like being in a dream again, and she felt a smile pull at the corners of her mouth.

Laying there, Rainbow was starting to wonder if something might be wrong, when Thunderbolt suddenly stood up. His knot dragged her face along with it, and Rainbow tried to fumble and find purchase before the knot pulled from her mouth with a pop. Slumping back down on her back, Rainbow was preparing to get up herself when that naughty tongue of Thunderbolt's lashed across her face. The smell of her own musky fluids assaulted her, and when she opened her mouth to berate Thunderbolt he shoved his tongue into her mouth.

Spitting and spluttering, Rainbow rolled across the floor twice and jumped to her feet. "What are you doing?! I could have… We just…" Silence filled Rainbow Dash, and she shook her head. "Okay, that was pretty amazing, but let's not do that again, okay?"

Thunderbolt just walked up to his bitch, and with a smile up to her, licked between her legs.

The parasite in Rainbow's head took note of everything, but nothing so much as how submissive her thoughts were, particularly when Thunderbolt had been on top of her. It didn't change anything, not yet, but plans were being assembled. Besides, it could recognize, in the girl's sense of taste, that Thunderbolt was likewise infected. There was no bond tighter or more fulfilling, than the one one parasite's host forms for another's host.

Rainbow stood in shock, and Thunderbolt just cleaned up the little mess she had made around her groin, then sat back. "This is odd, but—but awesome. Just licking, okay?" Thunderbolt just wagged his tail at Rainbow, and she couldn't help but swish her own back.

Staring at Thunderbolt, Rainbow felt a mix of emotions she couldn't completely understand. First and foremost was her affection for her pet. Thunderbolt looked dirty, though she could see past that to her friend, who had been with her for years. "We probably both need cleaning up."

Thunderbolt had gotten what he wanted, at least for now. Trotting after his bitch, they crossed the threshold that changed things. Led into the bathroom, he knew what was going to happen. Jumping up so his forepaws landed on the edge of the tub, he barked at his master.

In Thunderbolt's head, his parasite was working with the flood of food from the dog's orgasm. The amount of room in the dog's sub arachnoid space was much less than a human's, and the parasite was growing slower too. Nonetheless, it kept on with its work.

Rainbow Dash laughed at her pet, and got the water running. "Always loved the water, didn't you Thunder?" She roughed up Thunderbolt's neck and ears, and pressed against him. With her body naked and measured along his own size, Rainbow realized that Thunderbolt outweighed her by quite a bit. A shudder ran down her spine at the thought that if he hadn't dismounted her on his own, she wouldn't have been strong enough to get him off.

Shaking her head to free the image, Rainbow Dash shuddered a little. "In you get. You wash first." She reached forward and splashed her hand in the water, and before she knew it Thunderbolt was in the huge tub. "Good boy."

Thunderbolt's shampoo wasn't used as often as Rainbow's, but it was kept in the bathroom. Rainbow straightened up and walked to the vanity, and froze. "Whoa…" She stared at herself in the mirror, eyes studying every change her more advanced pony-up caused.

Her face was untouched, or so she thought at first. Leaning forward, Rainbow noticed her eyelids seemed a little more rounded, the point that her sockets usually formed near her nose were smoothed, curved.

Reaching her hand up, Rainbow ran it through the long mane of hair she sported. Her head might look a little strange without ears on the sides, but she was used to that. Having most of her head devoid of hair except for a thick stripe down the middle was new. Gone were the bangs that hung down the sides of her head.

Trailing down from her head, Rainbow smiled at her "girls." She reached a hand under each breast, and lifted them up to give more heft to her pert A cups. The most awesome change, in Rainbow's opinion, made itself known at the same height as her chest. Two wings spread behind her back, and thinking about them only made them stretch a little further. "I totally love this. I need to spend time working out how to use these properly."

Her mostly human brain tried to make sense of having a third pair of limbs, and all she kept doing was moving her arms, and her wings would mimic it. Frowning, Rainbow wrapped her arms tight around her body, and focused again. One little flap, and then another, but it was hard work, and her shoulders twitched to move too.

Author's Notes:

Thunderbolt: Do you think your master acting weird recently? What adjustment would you make to match your master's new routine (including sleeping in your bed unannounced) ?

"Woof!"

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So I do this "Ask x" thing, x can be any pony within the story. You can ask them anything and I they will definitely hopefully reply. Keep the questions appropriate to the age-rating of the stories and of course, I they will answer the best question(s) in the author notes of the next chapter. The more votes a comment has the more likely I will get it to the right pony to answer, try and keep it to one answer per post! I They will pick one question per chapter.

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