At the Castle of Friendship
Spike helped the injured creature through the door to the Castle of Friendship. He led her to one of the sitting rooms and set her down on one of the couches. He got a large fire going in the hearth to warm up his guest.
Twilight was away on business in Canterlot and left Spike in charge of the Castle while she was away for the week. Even if she was here, surely she wouldn't mind Spike bringing in an injured creature.
"There, the fire's burning nice and hot. How are your wounds?" Spike asked.
The cloaked creature sitting on the couch removed her cloak and revealed her species to Spike.
This female was a Gnoll, a species of hyena-like creatures native to the southern plains of Equestria and the northern parts of the Badlands.
She had a large and broad muzzle filled with sharp bone-crushing teeth, light tan fur with black spots, and long limbs ending in vicious claws. She was tall, too. Taller than Big Mac when she stood up. She had a noticeably curvy figure. She had breasts that looked like they could absorb Spike's whole head if he planted his head in her bust. Her hips and waistline were slim and her butt was perky accented by her short tail. Her attire simply consisted of leather straps covering her nipples and groin. One of her legs had a few bloody scratch marks.
The Gnoll girl looked at Spike with golden eyes that glowed in the firelight.
"I'm fine, dear dragon. The bleeding stopped" she replied.
Spike went and got a first aid kit and applied bandages to the wounded leg and brought her up the stairs to one of the guest room.
"Here you go. I'll feed you and check your wounds in the morning" Spike said.
"Thank you. What's your name?" the Gnoll asked.
"My name's Spike. What's yours?"
"Harley"
"Well goodnight, Harley"
The dragon then left Harley the Gnoll and went to his own room. Once there, he immediately went to sleep.
An Hour Later
The sound of a door opening, closing, and locking woke Spike up from his slumber. Rubbing the sleep out of his eyes, he breathed fire onto a candle and held it out. All he could make out in the darkness was a pair of glowing amber eyes looking at him. In the dim light of the candle, Spike could make out the silhouette of Harley standing there.
"Harley? What are you doing in my room?" Spike asked.
The Gnoll girl stepped forward into the light and smiled at Spike, showing off her fangs. She looked at Spike with half-lidded eyes and walked towards him with her right hand on her hip.
Spike's heart was pounding in his chest upon seeing the Gnoll walking to him like this. He couldn't take his eyes off of Harley for even a second. She was somehow... bewitching. Harley stopped directly in front of Spike and began to caress his chin with her left hand.
"I came in here to thank you for helping me, dear Spike" she said in a husky voice.
"T-t-thank m-me? H-how so?" he asked anxiously.
Harley's smile turned predatory. "Oh, you'll see"
In one swift motion, Harley ripped the entire blanket off of Spike's bed. The dragon instantly found himself sitting there on a bed with his previously-hidden boner on display for the Gnoll. He tried to cover it with his hands, but Harley grabbed his wrists and pushed them away from his groin. Harley grinned at seeing Spike's third leg.
It wasn't massive, but it could still get the job done. His hormone deficiency left him with a dick that was smaller than average and his voice sounded like that of a younger dragon. But Harley didn't seem to care.
"Aaaw! Your dick is quite cute, puppy!" Harley exclaimed.
"Wait. 'Puppy'? What's that about?" Spike asked.
"I don't want to ruin the surprise" Harley replied.
Without warning or hesitation, Harley dove towards Spike's dick and put it in her mouth. The way she was moving, one would think she was sucking on a popsicle. It felt so new and amazing for Spike.
Her fangs rubbed and brushed against Spike's dick as she moved her head from side-to-side. Her tongue curled to wrap itself around Spike's dick completely. Soon, she opened her jaws and began to lick both Spike's dick and his sack. Her tongue alternated between sucking Spike's dick and lapping up his balls. Spike could feel pressure building up from within his body and threatened to have it explode soon.
However, Harley stopped her blowjob abruptly. She moved her head up and gazed down at Spike.
"Sorry, but I can't let you come just yet" Harley said.
"Why?" Spike asked.
"I want to enjoy you first" Harley replied with a grin.
"What do you want me to do?"
"I want you to call me 'Mistress' "
"Okay, Mistress"
"Next, you have to follow my commands like a good puppy. Clear? Do that, and you'll get some treats"
Wanting more of the pleasure Harley can obviously provide, Spike got his hands and knees while gazing up at Harley.
"Yes, Mistress. I'll be a good boy" Spike vowed in a high pitch.
Harley grinned and proceeded to remove her clothes. Since her clothing was simply leather straps, removing them was quick and easy. Spike looked down at Harley's groin and saw something he didn't expect to see.
There was a dick. There was what appeared to be a dick standing at attention from Harley's groin. She waved it at Spike and pointed at it.
"I want you to make me feel good, puppy. If you do well and make me cum, I'll make sure you get a treat" Harley ordered.
Taking the hint, Spike moved forward and slowly engulfed Harley's throbbing pseudo-dick until he felt it probing the back of his throat. It tasted odd, but not unpleasant. It was warm and throbbing against his tongue. Spike decided to mimic what Harley had done and went about to please his Mistress.
He bobbed his head up and down on Harley's pseudo-dick. He used his teeth and tongue simultaneously to stimulate his new Mistress. And judging from her pleasured breathing, it was working. After a few more minutes, Harley made him stop.
Next, she got onto the bed, got on her hands and knees and showed her anus to Spike.
"Now, I want you to eat my ass" she ordered.
Spike dove in without any hesitation. He worked his tongue around the puckered opening and put a finger inside and twirl it. After that he used his incredibly long tongue and inserted it inside the opening. He could feel Harley clenching Spike's tongue as he moved it. Eventually, Spike pushed his tongue all the way up to the upper part of Harley's sigmoid and reeled it out. Harley was ecstatic. Spike thrusted his tongue in and out, getting faster and faster with each thrust. Spike's dick was getting harder with built up drive, but his Mistress will hopefully help him with that soon.
Harley turned, grabbed Spike's head, and brought it to her breasts. Spike was right about her sweater puppies. They did fully absorb his head when his head was between them. Spike found himself surrounded by nice-smelling sweater puppies that kept him warm and threatened to suffocate him. Spike massaged and kneaded Harley's boobs until her nipples were hard. Spike brought himself out and started suckling her breasts. Spike got more aggressive with his suckling until he could feel something hot and wet shoot onto his bare stomach. He looked down to see cum dripping down his chest and stomach and back up to see Harley smiling at him.
"You did amazing, puppy! I'm so proud of you" she said happily. "For doing such a splendid job, you deserve a reward"
"What's my reward, Mistress?"
"I'll make you cum. Get down on your hands and knees"
Spike did as he was ordered and he could fell Harley move his tail to the side. With no warning, Harley began to eat Spike's ass. His ass puckered and twitched at the new and exciting sensation. He felt Harley's tongue penetrate his sphincter and lap up the inside of his rectum. Harley grabbed Spike's cheeks and squished them beneath her claws. Next, she began to lick the space between Spike's anus and balls. After that was done, Harley used her pseudo-dick to tickle Spike's anus.
"Mistress! Please don't tease me! I'm begging you! Please put it in!" Spike exclaimed.
"Where do you want me to put it? Be specific, please" Harley replied.
"Please... put your dick in my ass! Fuck me up the ass with your thing! Turn me into your bitch!" Spike shouted.
"Alright! Here goes!" Harley shouted back.
Instantly, Harley shot her pseudo-dick deep inside Spike's asshole. He cried out in surprise, but eventually calmed himself. It felt so good having Harley's dick in his ass. It took up a lot of space inside his tight asshole, so Harley had to work a bit to move. His ass was relentlessly squeezing Harley's cock for what he wanted. After a few pumps to get Spike to relax a bit, Harley picked up the pace.
In and out her dick went. Both Spike and Harley were panting from the new sensations overwhelming them. Spike felt like his ass was being ripped apart and Harley felt like her dick was coiled by a warm and wet snake. Both of their climaxes were getting closer and closer to breaching. Harley continued to slam herself against Spike while Spike himself was feeling his organs rearrange.
Finally, Harley released her cumload deep into Spike's ass while Spike unloaded on the bed. Both of them cried out from the exertion placed upon them from the rough butt-sex they had.
"I've never... felt so good" Spike panted.
"Me... neither" Harley said.
Both of them fell onto the bed with a bounce. Harley laid directly on top of Spike until they both turned to their sides. Harley, despite her dick shrinking to its normal length, kept it inside Spike's ass. Spike could feel this and turned his head to speak to her.
"Why do you still have your dick up my butt?"
"You know how anyone with a penis gets morning wood? Well, I want you to wake up feeling mine inside you"
"Oh... okay. Well, we just had sex"
"Indeed"
"What does this mean for us now? Surely we can't go back to normal"
"I'll try to find a place here to live. Then we can fuck from sundown to sunrise. You can have all the butt-sex you want"
"Really?"
"Yeah. Your ass literally belongs to me, now. No one else can use it or eat it but me. Understand?"
"Yes... Mistress"
"Good. Now, let's get some sleep"
Spike and his new Gnoll lover fell asleep with content smiles on their faces.
Author's Note
Fun Fact: Female spotted hyenas have what only looks like a penis. It's actually an enlarged clitoris that looks like a penis. It's capable of becoming erect like a penis and the females have to give birth through them. Yeah, and human females think they have it rough.