"Twilight! Darling, I am home." Rarity pranced into the castle like she owned it, as she did with every castle in Equestria now. Because I own the very things that rule those castles. Rarity smirked at her systematic claiming of alicorns as pets. Something was wrong, where was "her" Twilight? Rarity trotted up the stairs and slowed her hooves as she crept up to Twilight's bedroom. Grunting sounds came from within.

Twilight had her snout pressed firmly to the floor, her plot in the air. Rainbow Dash had the big toy strap-on fastened firmly to her hips and was pounding the Princess' plot. "Well well, I come back a little early to surprise my pet and find her eating out of another's hoof." Rarity advanced into the room. For her part, Twilight had frozen in terror, but Dash was still pounding away.

Darkness seemed to gather behind the pristine white unicorn. "How delightful, we need to punish them both." The darkness itself spoke and finally got Dash's attention. She looked around, watching black smoke pour into Rarity.

As the pegasus pulled free of Twi and raced for the window, Rarity's horn lit. The window crashed shut. "Yes, sister, I think this punishment is beyond me. Our pet seems to want what I don't have, and little Dashie…" The dark smoke finished pouring in, staining Rarity's coat and mane. "Dashie needs a collar." Nightmare Rarity stretched her neck and sent out her power. The windows and the door began to glow with purple-black fire, boiling over them in sheets. "Dashie, Dashie, Dashie. You turned me down once, tonight I will brand you a Shadowbolt."

"Twilight!" Rainbow Dash watched in terror as the nightmarish incarnation of her merchant friend seemed to grow in stature, filling out a little. But the real thing that had Dash's attention was under Nightmare's belly. A thick stallion length had grown, stretched, expanded out to full erection.

Looking up and over her shoulder, Twilight gave a happy sigh. "Thank you, Mistress, I… should have waited. You left me too needy…"

Rarity, her mind full of the darkness that could twist an eternal alicorn, simply walked forward and over the Princess of Friendship. Rainbow Dash watched as that huge shape plunged down and into her friend. "Twi?" Dash couldn't look away, she watched as the nightmarish Rarity started pounding and bucking into the alicorn.

"Dashie… Dashie…" Nightmare Rarity looked back over her shoulder, even as her body pounded the braced alicorn. "You're next Dashie." The gaze paralyzed Rainbow Dash. She felt a wave of flushed fear and excitement both grab her. I don't want to be a pet, I don't want to be Rarity's pet. She would… she would… pound me with that... Rainbow's jaw hung open a little, her tongue soon flicking back and forth as she panted.

With her Mistress ramming her body hard, Twilight gave happy groans and whimpers, she wanted to be good but with all the enchantments her owner had laid upon her lately, she got horny all the time. "H-Harder… Please Mistress… Harder."

"Twilight Sparkle, you never, ever, fail to earn my forgiveness." Rarity arched back her head and poured magic out and into a spell. As her body unloaded into the princess under her, the Nightmare-touched unicorn fashioned more of her spell.

Rainbow Dash was frozen by the look of power, by the spell that was being put together. "Please let-" She got not another word out as the magic lashed out at her, flying for her throat. As the inky-black power circled her throat, Rainbow Dash felt herself tremble, felt a lethargy set in that seemed to radiate from her neck.

Nightmare Rarity dismounted from her pet, spraying the last bit of herself on Twilight's belly. "Now, how well did my spell work?" She turned and looked at the pegasus in the corner, watching her weakly struggling to pull the perfectly seamless collar free. "Oh, Dashie, come and clean Twilight."

Rainbow looked up, the words gave her a measure of energy back. She blinked and watched as the dark version of Rarity rolled Twilight over and unloaded again. A deep hunger rose in Dash, she saw Twilight's slightly puffy belly, saw the mess of fluids leaking from her and Rainbow's mouth felt dry, her throat parched. Her new "mistress" was crouched behind the oasis that Rainbow saw Twilight to be, she saw her Mistress and felt complete. The collar tightened a little more and Rainbow sighed happily, trotting over to do as she was commanded.

Author's Note

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