Dawn
Princess Celestia treasured the earliest, darkest hours of the day above all the rest. In the dim light, she lay silent on a broad cushion with her wings spread across its cloth and let the blues, greens, and pinks of her aethereal mane flow in the air while she focused on her wings. Using the pegasus magic that coursed through her feathers, she was able to gather a light fog to her chosen corner of the royal gardens that lay beneath the white and gold walls and towers of her Canterlot palace.
She quite liked how the dense branches of the tree above, combined with how her pale coat blended in with the ground-level cloud, rendered her almost invisible. Her personal guards had lost her when she combined a teleport with a signature-erasing spell, and they would never find her like this. Sadly, in not too many hours she would still have to return to the bureaucratic drudgery of her court and listen closely to the inane-to-asinine complaints, petitions, and declarations of its least worthy nobles for the rest of the day, lest any of them get a legalistic drop on her. For now, though, she was just a pony enjoying some privacy and tea.
Her cushion lay before a small wooden table she had built here in secret, hidden from prying eyes by a hedge that she liked to pretend the gardeners didn’t trim on this side every day. Charging her horn with magic, Celestia reached out and gave the sun another gentle upwards nudge. The world grew just a degree brighter, and the alicorn turned her attention back to the table and its pink-etched porcelain tea service. She took her time bringing the ingredients together, and filled her delicate little cup just right. The wrong amount of milk or sugar in her slightly bitter green tea wouldn’t ruin it, but the perfect combination was worth the care it took.
Once her cup was filled just so, Celestia inhaled the mixed aromas of tea, warming milk, and… a hint of rose? The pony who prepared her brews was spoiling her again; perhaps she would convince the palace steward to spoil him back with another raise. She smiled and levitated a spoonful of sugar straight into her mouth, letting the sweet rush drive her taste buds wild. Every pony, no matter how great or small, liked to do it from time to time, and this was her time.
“ ‘Gotcha.’ ” The gently-mocking voice belonged to the midnight-blue alicorn who, with her camouflage spell dropped and her tail swishing in unusual excitement, stood over the other side of the table. Celestia shrugged, licked the spoon clean, and set it down beside the saucer that held her cup.
“Good morning, dear sister.” Celestia looked up from her cushion, levitated her teacup to her mouth for a sip, and smiled once more. Luna, Princess of Night and Keeper of the Moon, was a welcome sight in more ways than one. "I trust all went well."
“Indeed.” Luna nodded. "Even had I not known from his dreams, Thunderlane's intent and his care for Rainbow Dash and Fluttershy are obvious. I made him understand the full breadth of responsibility which falls upon one who would own two bearers of Elements and tutor a Princess. His co-operation was full and immediate.”
“That's wonderful to hear. Thank you for taking care of him, and them, for me.” Celestia took another sip of her morning tea, closing her eyes and letting the warm drink rest around her tongue for a moment. She was mildly surprised when, on swallowing and opening her eyes again, she found Luna still present. “There was something else?”
“Tags.”
Celestia's mouth opened, then shut. That one word brought back memories, ones she was careful to re-shelve in short order. Working caution into her tone, she said, “So that is what you've been doing with the palace staff."
“You guess rightly.” Luna nodded again, a confident smirk growing on her muzzle. “I have been establishing the traditional play areas in preparation. Their reinstatement required new training to ensure that Thunderlane and his charges will be safe and respected—and that dear Fluttershy and Rainbow Dash will be properly tagged when they play.”
Celestia took another sip of tea while her sister spoke, and her tail flicked while she processed the information she was given. It was a minute before she spoke again.
“Very well. It is your right.” She took a deep breath. “I suppose I am still accustomed to ruling alone. Please, I would appreciate it if you kept me informed of your decisions.”
“That would have spoiled the surprise.” Luna's smirk twisted slightly as she lit her horn. Blue magic flashed around Celestia's throat, and a sturdy cloth strap tightened where the spell had struck. It was comfortable, and not constricting enough to choke. Celestia had to avert her eyes before she could speak again. She knew without looking what had been done.
“I know what this is. Luna, it has been almost eleven centuries. I…” For the first time in a decade, the Princess of Day was at a loss for words. The mere presence of her collar triggered long-conditioned calm and submission that clashed with her proud and willful nature. She swallowed.
“Hush, my Sunrise. I know your dreams too.” Luna walked around the table to stand over her sister, her wings spreading wide to beat once and dispel the fog. A breeze sprang up as though to meet her, and it made the field of stars that was her enchanted mane flow in the cleared air. It was like a living memory. Luna’s strength, her confidence, her magnificence belonged to the dominant sister of a millennium long past.
Celestia flushed with embarrassment—and a touch of warmth rose to her other end, too. Her thoughts of her sister had never been quite pure, even before she had grown weary of taking and losing lovers from among their shorter-lived subjects. She had turned to Luna. She had started this, and it had consumed her once. The intoxicating power that radiated from Luna’s form and high-headed posture was already taking its toll on Celestia’s will again, demanding her attention and compliance. She could say nothing.
Luna stepped closer, towering over her sister and their finest tea set. “Let me take this from you,” she said. She levitated the golden tiara from Celestia's head and sent it spinning off into the bushes, smiling when the most resistance offered was a wordless opening of her sister’s mouth.
“You have ruled long and admirably, my Sunrise,” Luna said. “Now you shall take a deserved and hard-won vacation; you will become accustomed to not ruling at all. You know that you, and Equestria, shall be safe in my care.” She smirked again as she teleported a special midnight-blue ear tag to levitate in between them. The tag was a flat, mallet-shaped design, identical to livestock tags used by ranchers except in color and material. In lunar-white print it read 000.
Celestia swallowed again. It was the first tag, and the only enchanted one. It had rested for a thousand years and more in a special case she kept in a hidden room with the rest of her most precious keepsakes. She still remembered what its magicks would do to her. One was a tracking spell, which was likely how Luna had found it again.
“You shall have nothing but life and love and pleasant, simple thoughts,” Luna said. She smiled down at her sister. “You shall be utterly mine, my good little puppy. I will fill your life with happiness and tend your every need. Put it on.”
It was inevitable, Celestia knew. Everything in her begged her to obey. Luna could back up everything she had said with ease. Even as she fumbled for words she could use to object, the elder alicorn found her magic taking over the levitation of her beloved tag and knew she was merely stalling.
“What of Cadance?” she asked, finally rising from the cushion. Her eyes were on the tag, now. Putting it on was not something she could undo herself; it didn't block her magic or suppress it, like many other disabling devices, so much as it made her forget how to cast even a flotation spell. “What of Twilight Sparkle? Sister, what of the sun?”
Luna tsked. “Cadance will understand. She can hide her dear little Gleam from you, perhaps, so far away—but not her dreams, not from me. And Twilight may require a most durable puppy to practice and experiment with; she will be confused, but curious.” Luna brazenly stepped around Celestia to steal her seat. Its near-blistering heat, the lingering radiance of her sister's body sat still for too long, bit into and warmed her muscles. She sighed in relief.
“Now, Sunrise, my precious pet, you shall kneel and put the tag on yourself. And some day, when you are needed or Equestria has forgotten that my beautiful puppy was ever their Princess, I might see fit to take it off again.” Luna grinned, her tail swishing playfully across the cushion. “Or perhaps, for my pleasure and yours, I may not. Not this time—not ever. But a good dog doesn't wonder if the sun will rise. She knows it shall.”
Celestia's breath caught in her throat, and a pleasant clench in her belly made her stumble. Her magic fizzled for a moment, and she nearly dropped the tag. Surely Luna wasn't serious! True, she had spent almost two centuries as a pet one time, after trusting Luna's whims before. True, she had never looked back on that occasion with the slightest hint of regret. But to give in again with the explicit warning that she might never be released...
The fire in Celestia's heart said one thing—the fire in her loins and muzzle, quite another. Her wit told her a third story: that of the tired old mare who trusted her sister and never again had to listen to another petty noble propose a purely self-serving law.
“Sunrise? If it is your pride alone that causes you to hesitate…” Luna smiled and took a sip of Celestia’s tea. Her voice softened. “I can break that for you.”
From the top of her spine to her tail, Celestia’s very core tingled wonderfully, and she shuddered. She hadn’t resisted a thing Luna had done—not the brazen disposal of her crown; not the exclusive use of her old pet name; not even the theft of her seat and drink. She knew what she wanted, and her ponies— Celestia took a deep breath, and found herself trembling in nervous anticipation. Her ponies had Luna. Her tag, Luna’s tag, hovered closer in the grip of her magic.
“You truly have become yourself again.” Celestia hesitated, tasting the next words, and found them once more to her liking. Her heart had changed its tune. “I’m glad to see you back… Mistress.” She wanted to be proud of her sister’s recovery. She wanted to say so—but it was no longer her place. Though slightly younger, Luna was once again more than her equal.
Celestia lit her horn with a second spell, reaching out for the sun. It was a few minutes early, but Equestria would live. “If you will permit me to raise—”
“No, Sunrise.” A thread of lunar magic crept through Celestia’s casting, its chill making her shiver and disrupting her attempt to lift the sun over the horizon. Luna’s voice was strong, and brooked no argument. “You cannot rule. You cannot care for the heavens. You cannot concern yourself with affairs of state. You are obedient and trusting, and you do as I say. You are my pet. You belong to me.”
Celestia knelt in the grass and took a shaking breath, catching faint aromas of earth and Luna’s lavender perfume. Her pulse sang the truth of every word. Her hindquarters were warm with anticipation of Luna’s dominance over every aspect of her life. Her mind raced with possibilities and worries—worries that, she admitted to herself, didn’t matter either way. She could still refuse, and nothing would come of it. Or she could obey and become utterly carefree, invulnerable to any shame for the consequences.
Celestia bowed her head and clipped the tag painlessly into her left ear.
Sunrise caught a familiar, wonderful scent and looked to her dark, beautiful Alpha. She yipped with joy, bounding back and forth in front of her reclining Alpha. Alpha was back, Alpha was back! It had been so long! Now everything would be the best! Her Alpha's mouth moved; somewhere among the jumbled noise, Sunrise heard walk. She knew walk! Walk was amazing! Walk was together with Alpha!
Rolling onto her back, Sunrise raised her chin to leave her throat vulnerable and show utter submission. When she found a leash clipped to her collar, Sunrise knew her Alpha had risen and it was time for walk. She hopped up again with a happy bark, and in her haste she briefly became entangled in the soft pink hair of her own long mane and tail. As the sun rose behind her and made the world bright, she let her smiling Alpha lead her across the grass towards the white and gold home that was Alpha's huge, stony den.