Even though Twilight knew it was futile, she indulged in a little pounding on the door above, yelling at Nightmare Cadance to let her out. It was, of course, completely ineffective … but she just really needed to work off a bit of the stress.

After that, she finally allowed herself to glide back down the long shaft, past the featureless crystal walls, and into the cell below.

Because that’s what it was. A prison cell. It may have been appointed with luxuriant drapes on the walls, soft carpeting, and plush pillows scattered tastefully around … but there was only one door, and it was locked tight, without any sort of doorknob or handle on the inside. It was just barely translucent enough to sort of see through … but all there seemed to be on the other side was darkness.

She of course tried the obvious: lock picking spells, trying to manipulate the outer latch telekinetically, blasting it with magic … but nothing worked. It certainly was true that Nightmare Cadance wasn’t thinking clearly, but it did seem that she was capable of designing a cell capable of holding an alicorn.

So … what did Nightmare Cadance have in mind for her, then? Was she just going to be left in here to rot? That didn’t sound like something Cadance would do. Not in her state. Surely it would be something love-related, right? So then why the delay? Was Nightmare Cadance focusing on Celestia and Luna’s romantic torment first? Was that it? Even though she’d have to admit the wisdom of dealing with the elder alicorns first, she couldn’t help but to feel slighted a little bit.

Or was that feeling disappointment? Her body raged from the inside out, her pussy still winking insistently. Oh, how she longed for whatever kind of love Nightmare Cadance had in store for her! She’d accept it, take it, anything to cease this—

No! Shaking her head, she fired off cleansing spell after cleansing spell, trying to free herself from the effects of the curse. But it was no use. Cadance’s spell had only activated her own body. The spell was long gone, and all the lingering effects were just Twilight’s own body betraying her.

If only she’d had centuries to master the art of self-control like Celestia and Luna had! She’d bet that they weren’t in their cell pining for Nightmare Cadance to send some lover to satisfy them! Surely they’d already mastered themselves and were working on an escape plan. As she herself should be. Only...

“Ugh!” She groaned, flopping down onto one of the pillows. Maybe if she just clopped herself very quickly, then she’d be able to think clearly enough to actually get out of here!

That wasn’t simple, though. As soon as she started touching herself, images of her brother’s cock came to mind, of him stroking it. No! She scolded herself. No, she couldn’t have that. She never could, not in the past and not in the future. If she could only stop thinking about it!

Think about Flash Sentry instead! She forced herself to think of the young man she’d met in her trip through the mirror into the human world … but it just wasn’t doing it for her. She’d never seen him naked, never seen him like that, stroking himself while staring right at her. And besides, those human bodies were just... Well, they were okay, but the proportions were all gangly and wrong. And Pinkie had shown her some of that world’s pornography while she was there. Human cocks were just … just tiny really, and strange-looking. She could imagine what Flash’s cock might look like for a few moments, but every time she really began getting into it, she’d find herself imagining a big, hard horsecock instead … and before she knew it, that was her brother’s cock, and then it would be on her brother, looking at her as he stroked it, as she stroked it, as—

No! She stopped herself, yanking her hoof out from between her hind legs and standing up again. Come on! Why couldn’t she just keep it together? Why couldn’t she control herself? The effects of Cadance’s spell were over! She should be able to get on top of this!

No! No again! She blocked out the mental image of her getting on top of Shining’s cock as he kept on stroking it just like she’d seen... No. She had to stay focused! Focused on—

High above her, the door opened again. She looked up, already unfurling her wings, ready to fly to freedom. Just in time to see Shining Armor hurtling down toward her, screaming all the way.

Instead of taking flight, she lit her horn, managing to catch him and slow his descent just quick enough. He still landed on one of the pillows rather heavily, but not hard enough to hurt anything.

And by the time she looked up again, the door above slammed shut.

“Shining!” she said, turning to her brother. “Are you okay? Did you—”

“I’m fine,” he said, picking himself up out of the pillow’s fluff. It had burst a little when he landed. He looked at her. “Oh thank goodness you’re here, Twiley – Cadance has gone crazy!”

“You’re … you’re you again!” Overjoyed, Twilight ran to him, wrapping her hooves around him and holding him close.

He hugged her back, holding her very close. So strong and snug... Despite her efforts to ignore his warmth and his stallioney scent, Twilight felt her tail rising even higher.

She tried to pull away from him, but he held her tightly. “Please,” he said. “Please don’t leave me alone. I don’t want to be under that spell again.”

Giving up her efforts to leave, Twilight hugged him again, nuzzling her face along the side of his neck just as she had when she was a foal. “I won’t leave you. Not ever.”

“Love you, Twiley.”

Why did that have to send such warmth coursing through her body? It was completely innocent! He’d said the same things so many times before. It shouldn’t be getting her excited now. If only her body would cooperate! “Love you too, BBBFF,” she said in return. Just the same kind of innocent thing she’d always say to him. No other meaning. No other meaning.

They pulled back a little, still holding each other, but now looking into each other’s eyes with a warm smile.

Shining leaned down closer, kissed her on her lips.

For a brief moment, she melted into it, her body rejoicing at the intimate touch of a stallion, especially one who felt so familiar and safe. Only a moment though.

When it finally got into her head what she was doing, just who she was kissing, she leapt backward. “Shining! No! Wh-what was that?”

He took a step toward her, looking genuinely hurt. “Twiley...”

She wanted to go back to him. Oh how badly she wanted it! She wanted to hold him, to comfort him, to stroke— No! She stopped herself again. No! And that’s when she saw it. The slight pink gleam of the love spell in his eyes.

Okay, no. No! She had to get out of here! Rushing to the door, she tried her whole litany of spells again. Of course nothing worked. But there just had to be a way! Because if she was trapped in here with him much longer, she just might...

No. No. She wouldn’t even think about it.

Shining was sure thinking about it, though. He came up behind her. “Twiley,” he whispered softly, “I need you.”

Her pussy winked hard at that, but she forced her tail to clamp down over it. Instantly she felt the wetness against the underside of her dock. “We need to get out of here!” she insisted. “Before... Before, um...” She clamped her tail down again – it had started to stubbornly rise. “We need to get out as soon as we can!”

“Twiley...” He rubbed his head over the top of her rump, his cheeks rubbing against her curves.

There was just no stopping it, not with that kind of warm and tender feeling, that kind of implicit invitation.

She couldn’t even bring herself to do anything when he pressed his chest against her from behind. The feeling of his warm chest fluff against her needy pussy was just heavenly. And when he slid up over her, grasping his forelegs around her, he just felt so powerful, so sure of himself. She could just melt against him, just let it happen. Oh she wanted it so much! When he nudged his hips forward, when the tip of his hot cock met just the perfect place, instantly plunging slightly inside her … that was when she finally woke up.

“Shining, no!” She darted out from under him, letting him slip back down to the floor. Her pussy winked like crazy underneath her tail, betraying her need.

He looked at her pleadingly. “Twiley, please...”

Oh that look on his face... The love spell must have been taking such a terrible toll on him. And he just looked so cute begging her like that. And after all, it wasn’t as if they’d never fooled around before. Maybe if she could just satisfy him a little bit...

“Look,” she said. She gulped and licked her lips. “Um... Will you be able to get your mind back in the game and help me open this door if I...” Deep breath. “if I just suck you off really quick?”

“You’d do that?” He rushed to her, hugging her again. The warmest, most genuine hug she’d ever felt. “You are the best sister ever!”

“Okay...” She slipped back down to the floor and nuzzled him a little. “Just make this quick, alright? We still need to get out of here.”

He nuzzled the back of her neck as she began to lower herself down underneath his belly. “Oh Twiley... You feel so nice...”

She hadn’t even touched him yet! Well, not the part that mattered, anyway. And that part that mattered … well, there it was. Right in front of her face now, throbbing and thumping up against his belly. Oh, he must have been so turned on! It wouldn’t be bad to just give him a little help, right? It didn’t matter that she was winking like mad under her raised tail, or that the feeling of him nuzzling his way down her back made her breath come short, or the way looking at his slightly upward-curved length made her legs feel weak.

Of course, it was only for his sake that she went to it so quickly, dipping her head down and taking his tip into her mouth. She just needed to get his mind off this. And maybe, well, get her own mind off it. His thick tip filled her nicely. So warm, so firm, and yet the skin was so delicate and soft. She slid her tongue along the bottom of his shaft, beginning to bob her head down lower on him.

Shining moaned softly. “Oh Twilight … so much better than the last time...”

The last time was when she’d just been a curious foal and – without knowing why at the time – wanted to find out what he tasted like. Oh, now that she’d had a little experience behind her, she could do so much better! She’d really show him how it was done, and she’d have him getting off in no time! There was some pressing reason for that, but it escaped her at the moment. What was driving her on at that time was the prospect of a big, heavy mouthful of her brother’s cum. She wasn’t sure why she was craving that so much, but it seemed like that would just hit the spot perfectly … and then maybe she could clear her head, too.

Soon, she was taking almost his entire length, sliding up and down slowly and luxuriantly. She’d taken smaller stallions down to the hilt before, kissing the sheath … but Shining Armor was a little on the bigger side. She couldn’t quite make it.

He didn’t seem to mind her missing the base of his cock, though. Groaning with satisfaction, he explored her body with one forehoof, sliding it over her back, around under her belly to tease her teats … and, of course, down around the curve of her ass.

Twilight let out a little moan of her own, squeezing it out around the girth of his shaft. Shining hadn’t hesitated at all to reach right under her tail and rub her pussy lips. How did it feel so good? She’d been touched before … why had it never felt like this before? The tingling pleasure shot through her whole body, emanating from under her tail but coursing through every part of her from hoof to horn. And it felt so wet and slippery back there. She’d only ever felt like this after using too much lube or something.

“Oh Twiley,” Shining said softly from above and behind her. “Why did I never realize how sexy you are?”

She wasn’t exactly in a good position to respond – her mouth was full. She gave him another little moan, though, pressing herself as deep as she could go on his cock, letting it slide far up her throat. The tender way he was petting her pussy made her want to get him deeper, want to please him as well as she could.

And it was working. She felt the bulge growing in her throat, his flare beginning to spread and choke her. She didn’t stop, though, even when her eyes watered and even when she couldn’t breathe anymore. She knew he was close. And his orgasm – now the only goal in the world she could think about – would be only moments away. She could do it. She could give it to him.

“Twiley!” Shining moaned deeply, pressing his hoof against her pussy and rump to push her deeper.

She let him, and she let him hold her there. Her pussy winked against his insistently pushing hoof, and just a little more of his length squeezed down into her mouth.

And then it throbbed. Twilight swallowed greedily, gulping down thick wads of her brother’s cum as fast as he could pump them into her. She could feel the thick tube along the underside of his cock pulsing with warmth, and she could see his beautiful, bountiful balls clenching right in front of her as they unloaded into her mouth.

She wasn’t done yet, though. Overpowering his push from her rear, she pulled back most of the way off of him, his still-pulsing cock glistening with her spittle. Just in time to catch the last few small spurts of it on her tongue, to taste his musky, salty flavor. Her pussy winked hard against his hoof, as if begging him to push it inside her.

But instead, he collapsed down onto one of the pillows, belly up and breathing hard. “Oh Twiley... Oh fuck... You’re so ... so... Mmmm...”

Her pussy winked again. She ached inside. A muzzy fog filled her head... She just had to get herself off if she was going to even have a chance of thinking clearly!

And oh, look... There was Shining Armor right there. His cock laid wet and limp against his thigh, but he could still help her in other ways...

Without putting any further thought into it, she climbed the pillow he’d collapsed on, swung her hind leg over him, and mounted his face.

“Mmm!” Shining said, his mouth full of sopping-wet sisterly pussy.

Twilight reached down and grabbed his horn, using it to hold his muzzle against her burning need. “I need this, Shining.” She moaned a little as his lips began to move against her slit. “And … and you owe me one.”

He didn’t put up any further fuss, opening his mouth and venturing his tongue slightly inside her, letting her juices slowly flow down into his mouth.

She rubbed herself on his face greedily, holding him steady with his horn, guiding him exactly where she wanted him … even though that wasn’t totally clear, even to her. She wanted his lips on her clit! She wanted his cute snuffly little nose rubbing along the outside of her pussy lips! She wanted his tongue plunged deep, deep inside her. It wasn’t deep enough! She had an aching need so far inside, right down at her core, and he just couldn’t reach it!

And that only made her ride his face all the more desperately. She needed more, so much more! Yes, she could get off like this – she already felt close – but it wasn’t touching that deep core of pent-up lust deep inside her. It wasn’t getting where she needed it! The only thing that could would be ... would be...

She glanced behind herself. Yes! Oh thank heavens yes!

Apparently, Shining had enjoyed being fed a hearty helping of his sister’s pussy, because his cock had grown again, emerging back out of his sheath to something quite nearly full mast.

She licked her lips. It didn’t require any thought, any consideration of the possible consequences. All that mattered was sating that deep need inside herself.

Shining let out a plaintive little whimper at first as she slid down off his face, but as she kept working her way down his body, as she neared his cock, that turned into a gasp of awe.

“Twiley,” he said desperately. “We... We’ve never...”

Twilight rubbed her soaking entrance against the tip of his cock. “We did, actually. Just a few moments ago. Don’t you remember? When you got up on my back and tried to put it in? Some of it did go in.”

“But … but that wasn’t—”

She pressed herself a little way down on him, her pussy lips opening around the tip of his cock and letting him get inside her just about as far as he had before.

“Oh... Oh Twiley.” He stared up at her adoringly. “You feel so good.”

“Just give me what I need.” With one long, sensual push, she slid down his shaft, letting it gradually slide up into her. It filled that yawing emptiness inside her, filled her perfectly. She didn’t stop until her pussy lips pressed down against her brother’s sheath. That’s where she paused, holding him there as deep as he could possibly be inside her.

His cock throbbed and moved a little inside her. His forehooves stroked up and down the curves of her body. His lips opened in a state of pure overwhelmed bliss. But he still seemed to understand just what was going on. “Twiley... I love you, but … but we’ve never done anything like this before. Are you sure it’s...”

Moaning, Twilight began to move back and forth on her brother’s lap. “I’ve never been more sure of anything in my whole life!”

At that point, Shining must have either agreed with her or just given in to the pleasure, because he flopped his head down against the pillow, groaning as she moved on top of him. He kept his hooves on her hips, though, squeezing the softness of her as she moved.

For Twilight, it was a truly transformative experience. Never before had she felt such a need inside of her, and never before had she felt it so fulfilled. She could feel every last little bit of her brother’s cock inside her: the blunt tip of it teasing her cervix, the medial ring squeezing back and forth across her inner walls, the thickly veined base of it rubbing her entrance in just the right ways.

She braced her forehooves against the pillow on either side of him, quickly beginning to move faster and faster on top of him, constantly yearning for just a little more of that sweet satisfaction she was finally getting. Her inner walls tightened around him, increasing the sensation even more.

Yes! Oh she was getting so close! Just a little more and...

“Twiley! Gonna … gonna cum! I can’t hold it!”

Already? It couldn't be! But she was already so close! “No!” she cried. “Just a little more!”

“Can’t...”

Could she keep going? Despite all the contraceptive spells in Equestria, she’d never actually let a stallion finish inside her before. Could she really let her brother be the first?

Did she have any other choice? She needed this! Once again, she started moving on top of him, his thick cock churning inside her.

“Twiley!” shining said desperately, now trying to push her up with his forehooves.

He wasn’t able to. From above, she had the advantage of her weight helping her … that, and she had a slight suspicion that he didn’t really want her to get off of him. And she sure wasn’t about to give up what she needed so badly! Already, her legs were tensing up to the point where they hurt. Her pussy was squeezing. Just a moment until...

Shining let out a desperate moan, his body jerking as his cum surged into her, coating her womb for the very first time.

The throbbing of his cock – and the knowledge of what it meant – finally set Twilight off as well. Her pussy clenched down hard around his shaft, milking it out of him, filling herself with his sweet warmth. And the orgasmic bliss exploding inside her sent that warmth coursing through her whole body. She had always been so close with Shining, but now, for the first time, she finally felt like she was one with him. The two of them were joined in an ecstasy that seemed to just keep coming and coming, each of them triggering aftershocks of it in the other.

Eventually, though, there were limits to what the flesh could provide. Even though he still gasped and trembled, Shining’s cock began to subside, growing soft inside her. And even though Twilight still shuddered and moaned, her tired inner muscles finally gave in to the fatigue. Shining’s cock slipped out of her, flopping limply against his leg again. This time, a small wave of cum fell from her pussy along with it. She shuddered again as she felt the warmth of it drip down her inner thighs along the side of Shining’s body.

She looked down at him. He looked back up at her. The two of them gazed into each other’s eyes as both of them breathed deeply, desperately.

And behind her, there was a slight sound. Crystal sliding against Crystal.

It felt wrong to tear her eyes away from Shining’s, but she couldn’t help but look.

The door was open! She stared at it, her jaw dropping. Then she realized what had triggered it.

“A door that’s unlocked by mutual orgasm...” She shook her head, beginning to pick herself up off her brother. “Only Cadance could think of something like that.”

“Cadance!” Shining yelped, suddenly leaping up off the pillow. “Is she going to be okay? Where is she? What if she—?” He just happened to glance down under Twilight’s tail, where she still winked a little as she dripped his cum. “Oh... Oh no. What if she finds out about what we did? She’ll … she’ll...”

“She’ll be fine with it, I’m sure. She was the one who threw you down in here with me, isn’t she?”

He nodded slowly.

“She must have planned all this out in advance. Come on. We’ve got to find Celestia and Luna. Maybe with all four of us working together, we can finally do something to stop her!”

Author's Note

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