(Yawn) "What happened, and why is it so dark?"
"Ah, good, you're awake." Came a voice from darkness.
"Rainbow? What's going on? Why can't I move? Why is my back so cold?-"
"Don't worry Kid, everything will be answered in time, but first."
All of a sudden, all the lights came on at once, blinding Scoot. Scootaloo squinted her eyes to protect them from the light.
Opening them, Scootaloo was shocked, Rainbow Dash was standing there completely naked, only covered by a ginormous strap-on dildo. Scootaloo realized it was the same strap-on she used on Rainbow's mom every time they fucked. Looking down at herself she also realized that she too was naked, spread eagle, strapped to a metal table with all her privates exposed.
"Rainbow Dash what's going on?" Scootaloo asked, scared.
Rainbow Dash trotted to a nearby table and grabbed a whip from it with her teeth. With the whip in her had she walked over to where Scootaloo was attached to.
(WHIP)
"Aaaah!" Scootaloo screamed from the pain, her body burning from Rainbow Dash whipping her.
"You refer to me as Mistress from now on Slave, you will be my pet and behave as a good pet should! Understand?"
"Yes."
(WHIP)
"Aaaah!"
"Yes what?"
"Yes, Mistress."
"Good. Now for why you are here." Rainbow Dash angled the table Scootaloo was strapped to so she was facing upward.
Rainbow, crouching so Scootaloo's vagina was right in front of her face. "Such a cute little cunt you have Slave." Rainbow stuck her wings inside and spread her walls open. "And very tight, don't tell me you're a virgin?"
"I, ah."
"I, what!" Rainbow yelled, slamming a hoof down on one of Scootaloo's puny teats.
"I am a virgin, Mistress!"
Rainbow Dash got up. "Well than, it pleases me as your idol and now Mistress to be your first." Aiming her strap-on dildo to Scootaloo's awaiting vagina. "Hm, I probably should get you wet first, but you deserve to be punished for fucking my mom you fucking slut." Rainbow Dash without any warning plunged the dildo deep into Scootaloo's womb.
"Aaaah!" Scootaloo screamed in pain from the pressure of the biggest dildo ever to exist in history entering her.
Rainbow didn't know how Scootaloo's tiny body could take that massive dildo all the way to the hilt and not have it come out of her mouth. "Impressive, Slut, very impressive. However I can't just keep it resting there forever, it's time for your rutting."
Rainbow moved her hips back and slammed them forward.
Scootaloo screamed at feeling the object ramming back and forth inside her. It felt so good, yet it hurt so bad.
"How do you like this, Bitch!" Rainbow said, panting with every thrust.
"It hurts, but I love it, Mistress." Scootaloo replied, loving her Mistress and how she's being treated more and more every time her Mistress calls her a dirty name and fucks her brains out.
“FUCK! Mistress, I love how you fuck me, you’re to kind."
“Am I you fucking bitch!”
Rainbow then Pulled out of Scootaloo before letting her climax reach its peak. She wanted her slave to scream. Walking over, she wheeled a table with a battery on it over to Scootaloo.
Scootaloo’s loins were churning with a mixture of excitement and fear.
Rainbow attached the electrodes to the battery, then to Scoots nipples and clit. After attaching them, Rainbow pulled a switch, causing a surge of pain mixed with pleasure through Scootaloo’s body, causing her to orgasm to release in an explosive amount of her pussy juice straight into Rainbow’s open muzzle, awaiting the delicious offering from her #1 fan.
“Not over yet Cunt.” Rainbow said, walking over to Scootaloo, still wearing the strap-on. Positioning herself on her face. Scootaloo could smell her own musk coming off of it, making her even hornier and willing to deliver more pleasure to her mistress than she gave to her. “Now it’s time for your prize, eat up.”
“Yes Mistress.” Scootaloo replied, licking Rainbow’s pussy.
Rainbow moaned from the pleasure she was receiving. Scootaloo was too good that Rainbow couldn’t hold back her orgasm. “Open wide and get ready for your treat, Pet.” Rainbow said, breathing heavily, while rubbing her pussy.
“Yes, Mistress.” Scootaloo said, opening her muzzle wide, ready to receive her treat that her Mistress was going to feed her.
“And don’t forget to swallow.”
“Yes, Mistress.” Scootaloo did as she was told, swallowing every bit of Rainbow’s cum, as well as licking the excess cum from around her muzzle and using her tongue to clean the inner most deaths of her Mistress’s pussy, causing a surprise orgasm from Rainbow Dash. This causes Scootaloo to start cleaning again.
This repeated until Scootaloo could clean both in and around her Mistress’s pussy without causing her to climax.
Exhausted and trying to catch their breaths, Rainbow didn’t bother undoing the binds and just laid her head down using Scootaloo's teats as a pillow.
“ How are you so good at eating pussy?” Rainbow asked.
“Mistress’s mother taught me.” Scootaloo answered.
“Oh, so maybe she too is meant to be a submissive slave and to please your Mistress.”
“Please, Mistress, I’ll do anything, anything you say, anything you want, I’ll let you do whatever you want to me if you’ll let me be your only slave.”
“Promise me that you’ll stop fucking my mom and I’ll let you please and pleasure me any time at any place, and I’ll fuck you." Asked Rainbow.
"I promise Mistress, I'll stop fucking your mom, I’ll please and pleasure you however, whenever and wherever as well as you keep fucking me like a bitch in heat. You were just amazingly awesome at fucking me, Mistress." Said Scootaloo.
"Deal, Squirt. Or should I call you Slave from now on?"
"Slave, Bitch, Cunt, Slut, Pet, call me anything you want to, Mistress. As long as I'm yours to do with as you please, Mistress."
Author's Note
This is the first clopfic I've written and I hope all you ponies enjoy and that every mare, filly, cult, and stallion get off on this. 
Feel free to write a sequel to this of Scootaloo's new submissive life to Rainbow Dash as her Mistress.
