Princess Twilight Sparkle was more than a little worried about what would happen when her lesson ended. She had spent the day measuring both Midnight and Twi's magic, and found them to be equal on knowledge, but Midnight Sparkle was far ahead on sheer intuition and power.

"Are we done, Your Highness?" Midnight's eyes gazed up at her teacher, and took in every curve. She found herself quite liking Equestria more than Earth, for a start there was a lot of magic here.

"We-We are for today." It took everything in Twilight to say the words. She firmed her resolve and managed to smile. "Let's go and have dinner, I am sure Spike has something good cooked for everypony." She used her magic to send the books she had used flying back to their shelves. She walked between the two desks where Midnight and Twi sat, and turned to Midnight on the way past. "You will have me alone tonight, but remember; a cranky and sleep-deprived teacher isn't doing their job."

"You are really going to be her…" Twi trailed off, staring at the other two ponies. "P-P-Princess, she is evil!"

Twilight sighed. "I know it might have seemed like it, but you really need to look at it from the other point of view." She looked at Twilight, then back to Midnight. "You both do. Come on downstairs, and be civil. I am only going along with any of this if you can both behave. The first sign I see of either of you misbehaving they are going back through the portal."

Twi nodded her head quickly, but was still a little unnerved that the demon she had feared—and had thought was gone—was very real and standing beside her. "Yes, Princess Twilight."

Looking from Twi to Twilight, Midnight felt a minor revelation; despite the Princess apparently having the power to "deal with her," Twilight had gone along with Midnight's request. It dawned on Midnight that either Twilight Sparkle was intrigued with what she had planned, or she was planning something. "Of course. I have more to lose than she does, I will be a good pony."

Smiling at her two charges, Twilight gave a nod. "Good. I really want you to enjoy your stay here, Twi." She looked pointedly at Midnight. "And I want you to understand that you are under no obligation to return to Earth when your training is done, Midnight."

The promise hit Midnight hard, and she found herself warming to Princess Twilight. "I don't ever want to go back. If I got stuck in someone's head again, I would go crazy." She turned and started walking after Twilight. "No offense." She tacked the last words on, she realized, for Twi's benefit.

Twi turned her head away from Midnight, still unable to look Midnight in the eyes after everything that had happened. Following Twilight Sparkle, she still marveled at how much easier it was to walk on four legs than two.

Twilight Sparkle sat down at the table, and picked the middle of the three seats Spike had set with pony meals for herself. "You are both every bit as clever as I am, but you need a lot more study to learn all that I can teach you of regular magic." The statement was loaded, and she knew at least one of the other Sparkles would bite.

" 'Regular magic'?" Midnight followed Twilight's lead, using her magic to wield her knife and fork. "What other kinds of magic are there, then?" She speared some stir-fried vegetables and levitated over some soy sauce to dash over her bowl.

"Well," Twilight went heavy on the sauce for her own bowl, "regular old unicorn magic—what I am teaching you now. Then you have alicorn magic, shadow magic, song magic, cutie mark magic, and finally the most powerful." She left both her companions hanging to munch on a fork full of food.

Twi was just as caught up in finding out more as Midnight was, and was the first to clear her mouth. "What is the most powerful magic?"

"Friendship." Twilight grinned. "Oh, hello Spike. This food is wonderful!" She beamed at her Number One Assistant.

Midnight blinked. "Friendship magic?" She scraped her fork around the bowl to search for more of the little green sprouts that tasted fantastic. "What's so special about friendship?"

"When ponies work together with their friends, literally nothing can stop them." Twilight used her fork to point at one of the big stained-glass windows. The scene portrayed had Twilight in a circle at the top, and below that the huge form of a centaur. "Tirek had all the most powerful magic in Equestria. He had all the princesses' power behind him," Twilight grinned as she remembered, "but he tried to threaten my friends."

"Wow." Midnight stared at the window, and realized there was several more all with Twilight and/or one of her friends triumphing over a baddie. "Remind me never to get on your bad side."

"You came close. You put that thing on Twi." Twilight had to hide her shudder at what thoughts the device had inspired in her. She wanted to feel it on herself, to fight the thing and slowly lose.

"Well, it's a good thing we all calmed down a little, but I will have my fun regardless." Realizing just how close she had come to being sent back to Earth, Midnight missed Twilight's little shudder. She scooped up her next mouthful and was surprised at a sweeter taste to it. Inspecting the food, she pointed her fork. "Are these flowers?"

"Yup!" Spike cut in, gulping down the gems he had been chewing up. "I got them in town fresh while you were having your lessons. Roseluck said they were picked early this morning."

Their meals ended, Twilight Sparkle started to excuse herself from the table. "I am going to be doing some extra study with Midnight, Spike, and we might be up a little late with it."

"Twilight, Rarity told me about the… deal." Spike looked at Midnight Sparkle, then back to Twilight. "I like it about as much as she does, but Midnight seems to be a lot less… crazy than Rarity said." He waved his hand in a circle. "We are all adults, but even though you agreed to this I won't let her hurt you." Staring at Midnight, Spike used the most serious voice he had. "Don't hurt her, or you will have a dragon to deal with!"

Looking first to Twilight, Midnight turned to face Spike. "I will play with her as much as she lets me. If I hurt her, Sir Dragon, I expect quite the fight ahead of me." Midnight would have said and done anything in the past, to break free and get what she wanted. But now the dark alicorn had everything laid out for her on a plate, so she didn't have to hurt anybody.

Spike's honor was maintained, even if the subject was a little more than he usually liked. Getting up, he began scooping up the plates and cutlery.

Twilight's heart was thudding in her chest. She took a deep breath and tried to steady herself. "We will spend the morning investigating the things from your backpack, Twi." She turned her attention to the former human. "And continue magic lessons in the evening, if that is okay with both of you?"

"That would be great." Twi perked up at mention of both experiments and magic. "I really want to see what happened to my phone. Do we know if all the rules of physics are even the same here?"

Midnight couldn't stop herself from getting a little excited too. "After we verify everything, we can try testing magic on them."

"We will have to write up some hypotheses for experiments." Twilight was just as excited as Midnight and Twi, and was happy to indulge in it a little. "I think the first thing we can test is gravity, should be easy enough to measure, too."

"But that is tomorrow." Midnight ruffled her dark wings a little, and stared at the Princess. "Goodnight Twi, we will both see you in the morning." She gave Princess Twilight a hungry look, and turned for the stairs that led back up into the more private parts of the castle.

Hurrying to catch up, Twilight fluffed her wings a little in trepidation. "Good night, Twi." She turned to give Twi a smile before chasing after Midnight. "What are you going to do to me?" Twilight couldn't believe she was going through with this, but she knew if she didn't try it she would be forever regretting it.

"Eager?" Midnight purred the word out. "I am going to take away everything. All your power will be redirected against you, you will be my plaything for hours." The words had different effects on both mares. Midnight felt her arousal grow and ached for the control Twilight had promised, while Twilight let out a little gasp at the description. "Are you ready to back out on our deal?"

"No!" Twilight knew she replied too fast, but when Midnight's dark wing reached out and over her, she was so glad she did. "Twi might have thrown you out of herself, but… there is a little of you in me. I want to see what it feels like, even if it is just once." She voiced her private thoughts, and opened the door to her bedroom to show Midnight where to go.

"Good girl." Midnight drew Twilight along under her wing, turned, and pushed the door closed with her own magic. "No more magic for you. If you cast anything, I will start early."

"Early? What do you mean?" Twilight was a little confused. Her eyes widened when Midnight's horn flared, and a tight grip closed around her own throat. Twilight gasped a moment, but the collar wasn't restricting her airways.

"While this is on, you are my pet, and I am your master. You will address me only as Mistress or Mistress Midnight." Walking around Twilight, Midnight looked over the mare. "This is now our bedroom, mine when you have the collar on, do you understand?"

Twilight's voice wavered a little, and she gulped past the collar. "Y-Yes Mistress Midnight." The words didn't sting to say, quite the opposite. She practically melted within her own head. "But M-Mistress, I read in a book that we should have safe words and—" A dark hoof lifted and pressed gently to Twilight's muzzle.

"We are going to start slow tonight. You want to feel everything at once, but you aren't ready." Midnight wanted to leave out that she didn't quite feel ready either. Her "worse half" had never so much as looked up a dirty magazine, so Midnight was left with her imagination as to what she should do. "Stop is something you might want to yell, so…" She pondered. "What about 'rush.' "

"Rush?" When Midnight nodded, Twilight beamed. "Thank you, Mistress Midnight." Again just saying the words sent a tingle up and down Twilight's spine.

"Now, the rules are simple; do what I say, when I say it." Midnight looked into Twilight's eyes. "Tell me you want me to bind you up."

Twilight blushed hotly and her throat trembled. "I… I do want you to bind me up."

"Mistress." Midnight "You must always address me properly. That will cost you one hoof." She flared her magic, all the power of an Equestrian alicorn rushed through her, poured through her horn and out.

"Sorry Mistress!" Twilight tried to correct herself, but it was too late. Midnight's aquamarine magic shot out at her back leg, wrapping around it and squeezing it. Thick, hard rubber encased Twilight's leg. She could barely move the limb within the tough covering. "S-S-Sorry… Mistress Midnight!"

"Now you are learning. How does it feel to be at my mercy?" Midnight walked around Twilight some more, and when she was behind the pony she grasped her tail with her magic. Lifting the mass of hair, she investigated it. Feeling slowly up the Twilight's tail, she found her dock. Her magic grip solidified into more of the rubber, but this was elastic, and linked the mare's tail to her collar.

"It feels… it feels good, Mistress!" Twilight felt the cool air over her rear, but when she turned to look at what Midnight had done, her tail was yanked sharply up her back. It wasn't hard for her to work out that she was going to be keeping her tail way up in the air, and her head forward. "M-M-M…" Twilight fought with her voice. "Rush!"

Midnight immediately let go with her magic. "What is the matter?" She walked around Twilight, running a dark wing along the alicorn's back.

"Sorry, I just… it feels good, but I need a little more stimulation…" Twilight started to lower her head, but jerked it up straight again with a blush. "Maybe something to… to make me horny?"

"You loved that hood I put on Twi, didn't you?" Midnight watched her little pet's blush deepen. "It's alright to tell me, if you tell me I can work something similar for you. Twilight Sparkle, tell me you want me to make you achingly horny."

"I really want to feel like that, Mistress." Twilight knew the game was back on the moment she addressed Midnight as "Mistress" again, with her desires made known, she wanted things to continue. "Please Mistress Midnight, I want you to make me ache in pleasure." She made a point of bowing her head a little this time, putting up with her tail hiking further and further up.

"Well aren't you such a good girl for asking so nicely?" Midnight leaned forward and kissed Twilight's horn. Power flowed, and Midnight channeled it, like with Twi last time, into forming a bridle around Twilight's head. Rubber flowed from her magic to bind around the Princess' muzzle, around her jaw, and then the back and top of her head.

Twilight could feel each part of the bridle pull tighter and tighter, but she still had her magic. Where the rubber came down around her mouth, she felt it start to dimple inwards, pressing at her cheeks and finally into her maw. The rubber crossed from one side of her mouth to the other, forming a loose bit. "Fank woo Mishressh!"

With her pet physically secured, Midnight knew the last thing her plaything wanted was the finishing touch. "Your night will be dark, from here on out." As she spoke, Midnight massaged the rubber down over Twilight's eyes, plunging her into darkness.

Twilight was trapped in a web of her own choosing. She had to give up on controlling her breathing, and panted hard. An odd sensation, of something trickling down her uncovered back leg confused her for a moment, until she realized she was so aroused that she was leaking. The moment Midnight's magic touched her horn, Twilight nearly orgasmed in delight. She squirmed as the magic poured rubber over her horn.

"It's done, pet." Midnight used her magic to gently brush Twilight's mane back from one of her ears. "You are on the slow path to a very naughty night. You can have two hours like this, and then I am taking it off you."

The effect of the horn-guard was subtle; Twilight could barely feel her magic being slowly sapped by it, drawn away and worked into arousal-causing enchantments. She wanted to know how Midnight had come up with it, but in the one day of teaching she had discovered the mare was a savant with magic. She channeled, just a little, and groaned appreciatively.

"Oh, you tried to use your magic?" Midnight powered her own horn and bound Twilight's other back leg up in hard rubber—adding a spreader bar between the stuck limbs for good measure. "Do you want to use your word, Princess Twilight Sparkle?" She walked around behind, and found Twilight's vulva leaking great drips down her rubber-coated legs. A pony's vulva was very different to a human's, but Midnight wanted to taste her pet so much she really didn't care. "Mine."

Twilight moaned into the bit as Midnight started to lap and lick at her. She felt her clitoris wink again and again at the near-constant pleasure rushing through her. Slowly, Twilight's mind narrowed its focus down to the increasing lust, and she just let go of all her worries and submitted.

~~~~~+++++~~~~~

When sleep shoved back from Twilight's head, she was still muddle-headed enough that she forgot all about the previous night, until the moment she opened her eyes and was snout-to-snout with Midnight Sparkle.

The rubber was all gone, her arousal was nothing more than a warm fulfillment that she had enjoyed herself a lot before sleep. Slowly, her thoughts traced down and drew her memory of what had happened back to her. Her Mistress voice demanding Twilight service her, the taste of Midnight's body, the taste of her own on Midnight's tongue.

"Good morning, Princess." Midnight smiled widely. "I hope you slept well?" She lifted a hoof slowly, tracing it up Twilight's barrel.

"Y-Y-Yes, Mis…" Twilight blushed hotly. "Yes, Midnight." She smiled, she hadn't felt this relaxed since… well, ever.

Author's Note

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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