Even with an orgasm tingling its way through her body, Twilight Sparkle could recognize the tone of somepony in distress. She had had a little more experience since her disaster with Fluttershy, and didn't need to hear Sunburst say "Red" to know he needed a pause.

Twilight huffed for breath. She could feel the toy sending the last few spurts of hot goodness into her (prolonging her orgasm a little), and had to just ride out the release. Turning her head, she looked up at Sunburst, who she devoutly believed was the donor of the seed that had just impregnated her. "What—What's up?"

"Y-Y-You don't understand, P-Princess. That isn't mine." Sunburst pointed a hoof at the canister that was now showing only two-thirds the amount of semen as Thunderlane had put in it. "We—I—He…" His voice trailed off.

Reaching up with her magic, Twilight guided Sunburst to lay down beside her. "Tell your mistress what you did. Every detail." She used one hoof to stroke her own belly, feeling a slight swelling that she knew would go down after she cleaned up, and return as she swelled with foal.

Sunburst turned his head for a moment, looking to Starlight, but Twilight's magic took hold of his head and turned him back to look at her. "W-We got to talking about this—about Starlight having my foal—and I might have mentioned something that has always turned me on: cuckolding."

"Who would you cuckold?" Twilight's brain whirled with choices, and she couldn't help but think of the obvious solution. "You wanted to cuckold Shining?"

"What? No!" Grabbing a pillow, Sunburst tried to hide under it. The effect was more adorable than effective. "I wanted to be, well, cuckolded. We talked, and Starlight said that if we were having a foal anyway, why not have another stallion's."

On a new track, Twilight's brain actually followed the correct path. Her eyes widened. "Who did you…?" As she trailed off from here question, Twilight's head turned, and her eyes focused on the toy still inside her. As if sensing her inquisitiveness, the toy let out a little jolt of seed into her body. "Whose is it?"

Sunburst hung his head. He looked down at the pillows under Twilight and murmured Thunderlane's name so softly even he couldn't hear it, let alone Twilight.

"Louder. Tell me the name of the stallion whose foals you are going to help raise." The time for worrying would be later, Twilight decided. Right now they were in the middle of a scene, and she had just discovered a kink of one of her subs. "Which stallion took your right of fatherhood from you?"

Freezing at the question, Sunburst looked at Twilight with wide eyes. He felt like a deer in headlights; he had just revealed a massive screw up that had let to the Princess likely being impregnated by the wrong stallion, and she was playing it off as part of their kinky scene. He gulped.

"Th-Thunderlane." Sunburst's throat felt dry.

Twilight's ear twitched. She had heard him, but wanted him to tell her more clearly. "Louder. Tell your mistress who has gotten her pregnant instead of you."

The chill of the situation snapped, and Sunburst stared with wide eyes and a growing erection at Twilight. "Thunderlane. I wanted him to sire a foal on Starlight, M-M-Mistress."

"But now we have a situation, don't we?" Twilight used her magic to ease the hefty toy from her body, sliding it out. "Your mistress wanted your foal, not this other stallion's. Should we make it a contest? Should I make you climax in me now, and leave the foal's siring up to chance?"

The thought of not knowing, as the pregnancy progressed, was like a hard knot inside Sunburst. He lowered his head as Twilight stood, and she towered over him. If it was so wrong, why did it feel so good? Sunburst thought.

Levitating the strap-on harness over, Twilight attached it to the big toy. "No. No I want no chance. You can't be the sire of our foals, but you will be their father." Using her own hooves, Twilight adjusted Sunburst's position, pulling him upright, making him stand before her.

There was something amazingly intimate about a unicorn—or alicorn in this case—using their hooves to do something. Sunburst let out a little groan as he was repositioned, and his rock-hard erection was put on display for all to see.

"Perfect." Twilight reached under Sunburst and stroked his shaft with her hoof three, slow times. "You are going to be using this." She leaned in closer, pressing her snout against his tucked-back ear. "And this." While she had been stroking his shaft, she had positioned the strap-on underneath him, and now it latched on.

"Princess!" Sunburst squealed like a filly at her first kiss. Twilight's magic bound the straps around his hindquarters tightly, leaving him with the appearance of two shafts—the fake one hanging under his own.

"Wet Nurse!" Twilight's voice had a sing-song tone to it.

Starlight, trapped in the cycle of lust the enchanted outfit had worked her into, lifted her head at her mistress' call. Through the haze of need and enforced desire, she spotted Twilight and Sunburst. Like a haze lifting, Starlight beamed at her mistress. One foreleg moved, then the other, but when Starlight's back legs moved she found her udder was full again, and she was forced to waddle.

Patiently, Twilight waited as Starlight made her way across the room. Waiting until Starlight was almost to the cushions, Twilight used a new spell she had been working on to soak Sunburst's shaft in thick, slick goop. "I think you know what I am going to have you do, Sunburst."

Sunburst's eyes widened; it all made sense now. He nodded slowly and took a step towards Starlight. "I am not allowed to use her pussy, am I, Mistress?"

"You are not. That is for the toy. You can have her rear, instead." Laying back down, Twilight reached a forehoof down behind her back legs and started to stroke her messy folds.

A new measure of steel filled Sunburst; he was actually strutting. He realized now what the pull of this kinky stuff really was: he wasn't the one doing things. Sunburst wasn't going to screw Starlight Glimmer and impregnate her with another stallion's foal, Princess Twilight Sparkle—his mistress—had ordered it, so it would be done in her name.

Starlight was barely able to keep herself on all fours, so when Sunburst jumped up on her back she almost collapsed. Turning her head proved to be the undoing of her forelegs, and Starlight felt her barrel push down to the floor under Sunburst's weight.

"Let me help you." Twilight used her magic to grasp both Sunburst's real dong and the fake one. When the stallion bucked forward, Twilight lined both shafts up perfectly.

The second the flared head of Sunset's penis kissed Starlight's ponut, instinct took hold. His hips bucked, his back legs jumped forward, and he drove himself and the toy into Starlight Glimmer's body at the same time. She was angled down, which meant Sunburst could lean over Starlight rather than riding her back. It also gave him a mechanical advantage while shoving into her.

Overwhelmed by the sensation of being double-filled, Starlight wanted to encourage Sunburst, wanted too to put on a show for her mistress, but in her already over-aroused condition all she could do was brace her back legs and provide a suitable platform for Sunburst to rut into. She closed her eyes, the very picture of bliss.

Stroking herself toward another climax, Twilight watched Sunburst screw Starlight like a beast. Both his own shaft and the toy shoved into the mare with each grinding thrust, and Twilight could see Sunburst's muscles strain to pull both free again.

Losing himself to the lust of a stallion in rut, Sunburst listened for commands from his mistress and moans from Starlight both. He drove himself to frenzy with each shove forward, and could feel his orgasm approaching.

As Sunburst's thrusts became more erratic, Twilight rubbed herself more firmly, and her clit winking out to meet her hoof. In the back of her mind she made a note to train Sunburst to have more stamina, but given the kink she was letting him play out, she wasn't surprised he was losing himself quickly.

From one hard thrust to the next, Starlight felt a wash of heat blossom in her rump. She opened her eyes wide, and let out a deep, satisfied moan. Sunburst seemed intent on pushing himself as deep as he could, and Starlight could feel his belly pressed to her rump as the heat grew.

Then Starlight's eyes fluttered closed as an equally hot rush of liquid flooded into her vagina. Instinct drove her forelegs to action, and she began pushing back into the stallion of her dreams. With a delighted mewl, Starlight felt herself pushed over the line into her own orgasm.

The heat inside Starlight seemed to radiate through her body, spreading out from the center of her being to encompass all of her. With each extra blast of heat into her, the inferno intensified. It was impossible for her to keep control, and she surrendered to the lusty mare that lived within.

As Twilight watched Starlight's orgasm wind down, she tapped her chin with a hoof. "Oh, right, there's still one charge left." Rolling off the cushions, Twilight walked towards her submissives, her hips swaying at how in control she felt, and began undoing the straps of Sunburst's strap-on.

There was a conjoined cry of surprise as Twilight pulled the toy out of Starlight and from under Sunset. Both ponies turned to look at their mistress. Twilight, while they watched, began fastening the straps around her own hips.

"You have both been good little pets, and while we need to talk further about the contents of this toy—after I made it explicit whose seed it should have in it—there is still one of us who is missing out on Thunderlane's gift.

Sunburst had never really thought about other stallions as sexual partners—he was as straight as they come—but he had a sinking feeling he knew just where Twilight was going to put the toy, vigorously.

Twilight practically swaggered up behind Sunburst. Before going further, she cast the lubrication spell again, but rather than target the toy under her, she targeted Sunburst's rear.

A warm deluge of fluid washed up into Sunburst's rear. He knew his squeal was more than a little girly, but that was the typical consequence when a stallion was lubed up for the first time. He hadn't been commanded to disengage, and so held his ground over Starlight—inside starlight.

"Color check." Twilight spoke the words softly, but could see Sunburst's ear perk at the sound. She waited, not wanting to go further without his approval.

Sunburst had to fight back his urge to stop Twilight with a Red signal. Everything she had done with him so far had been either really fun or at the very least tolerable. Who better to give your anal virginity to, after all, than an alicorn? he thought. "Green. Yellow-green. Be gentle, please."

Starlight felt as Twilight began to push into Sunburst. She felt him jostle forward a little, then pause in his attempt to get away, and finally she felt him try to push back and pull free of Starlight's ass. But Twilight was too far for him to disengage, and Starlight felt him push back into her as Twilight's hips forced him to.

Memories of seeing stallions having sex clouded Twilight's thoughts, and though she wanted to shoo them away, she knew they held the answer to what she wanted. The dominant side of her was in heaven, and before she even realized it, she pulled her hips back and pushed in again.

It wasn't the feel of the shaft, for Twilight couldn't feel through it (not really), but the little sounds Sunburst made with each thrust she made. His worried whimpers had lasted two thrusts, then they had turned wanton. His voice sang to Twilight's ears, urging her onward, guiding her pace inside Sunburst.

Sunburst let himself be shoved around, forward with each thrust from Princess Twilight, and backward when the Princess' shaft dragged from him. His own length seemed an afterthought, though it was planted in Starlight still—and she made happy sounds when he moved—all his attention was on his rear.

"I won't stop until you climax again." Twilight had to grunt to get the last few words out. Any normal unicorn would have quickly tired from the odd motions, but Twilight Sparkle, Princess, held the stamina of an earth pony in her body. She kept her pace up, settled into a rhythm, and plows up Sunburst's rear.

The orgasm rushed up on Sunburst again. One moment he was the filling of the "powerful mare sandwich" and the next he was oozing out everywhere, but mostly of Starlight. Heat exploded in Sunburst's rump, a strange warmth that he instinctively knew was another stallion's seed. Thunderlane's seed.

That both Twilight and Starlight were likely pregnant to the other stallion was one thing, that he—Sunburst—was now full of the other stallion's seed too was icing on the cake. His flagging orgasm seemed to swell and build further, and he actually whimpered as he exploded a third time into Starlight's rear.

"Cadance?!" Shining Armor found his wife staring into a scrying mirror with one hoof behind and stroking her vulva. "What are you doing? Who are you watching?" They were in the royal bedroom in the Crystal Empire, it was evening, and the room was filled with the scent of aroused alicorn princess.

"Just checking up on a student, Shiny." Cadance used her magic to disengage the mirror, and turned to her husband. "More of a warm-up, really." Her tone held the promise of a long night ahead for both of them.

"Did they pass?"

"Oh boy did they pass." Cadance almost pounced on Shining Armor.

Author's Notes:

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