1: Not the best Introduction
Gleaming Shield figured she had everything she could ever really want from life. She had fulfilled her fillyhood dream of joining the Royal Guard, and was well on her way up through the ranks. She had landed a cushy post in the Royal Library where she was frequently visited by her little sister, and best of all, she had finally scared most of her colleagues enough to get them to stop staring at her butt. What more could she possibly wish for?
Well, if she was completely honest with herself, some adventure would be nice. Her guard duties were certainly fulfilling, but they were a far cry from the grand exploits she had read about as a filly, inspiring her to join the age old institution of protecting princesses. Of course today, the phrase "be careful what you wish for" kept floating around her mind as she hustled toward Princess Celestia's office.
The day had started like most others, wake up, get ready, report to the library, read books when no one is looking. It was in the middle of her stealth reading that Gleaming had been startled by a strange muffled voice behind her, enough to cause her to yelp, slam the book closed, and fall haphazardly from her chair while attempting to stand and snap to attention.
From her position on her back, she could now identify the source of her unpleasant surprise to be one of her fellow guards, luckily one beneath her in rank. "I'm sorry what did you say?" she asked sheepishly, scrambling to get back up on her hooves.
The stallion rolled his eyes before pulling the sealed letter from his mouth and holding it out towards her. "I said, message for you ma'am. Apparently it's urgent."
Forgetting her mild embarrassment in a fit of curiosity, Gleaming took the missive and gave the guard a quick nod. "Thank you, you're dismissed." The guard nodded as well and trotted off towards the library exit now that his task was complete, though she hardly noticed. Her entire attention was now focused on the royal seal adorning the face of the letter. She quickly tore open the envelope with her magic and extracted the small parchment within.
Corporal Gleaming Shield,
At the request of Her Majesty the Princess Celestia of Equestria, you are to report to the private royal offices for temporary reassignment. You are expected as soon as possible.
-Lord Commander Silverwing
Gleaming's eyes nearly popped from her head as she read the brief message. She had never even seen the Lord Commander in person, let alone been given direct orders from him, and orders to report to the Princess no less.
Stuffing the letter into a pouch beneath her armor, she began a brisk canter from the library towards the diplomatic wing of the palace, trying to restrain various wild imaginations of what the nature of her new assignment could be.
~~~~~~~~~~~~~~~~~~~~~~~
Gleaming stood straighter and more at attention than ever before in her life. This was, after all, her first time reporting to the Princess as a guard.
Across from her, sitting behind a large wooden desk, Princess Celestia tried to hold back an amused fit of giggles and maintain a mask of calm professionalism. While hiding her emotions was usually easy for her, this situation managed to tickle her in just the right way as to make it impossible. Finally she gave up, an enormous grin cracking across her face. "Gleaming, relax! You look like you're about to pull a muscle from standing like that."
Gleaming frowned as she let her backside plop down into a sitting position. "Princess, this is supposed to be serious! You promised you wouldn't treat me any differently then the rest of the guard once I graduated the academy!" She crossed her forehooves and let out a huff, which in retrospect did not improve on the impropriety of the situation. "When I'm on duty, I'm just a guard, and you're the Princess, not Auntie Celestia."
In truth, they had known each other for many years, and with the Princess essentially being a second mother to Twilight, she had sort of just been absorbed into the family, at least when the public wasn't looking. Unfortunately, this had led to many ponies crying favoritism anytime Gleaming experienced even a hint of success, and years of it had made her stubbornly adamant about being treated just like anypony else. Of course, this had just resulted in Celestia stubbornly trying harder and harder to spoil her 'niece' against her will.
The Princess sighed, but not without losing the smile on her face. "Oh fine, I'll play by the rules." She said as she took a step around the desk and gave Gleaming a quick nuzzle, which Gleaming returned, fighting to keep her glowering expression intact. Just as quickly Celestia returned behind the desk, cleared her throat, and put on her best all-powerful-ruler expression.
"Corporal Shield, Princess Twilight Sparkle is expecting a visitor to her hometown of Ponyville, a visitor of grave diplomatic significance. Both her and I have agreed that said visitor, while welcome here in Equestria, must have an official escort at all times. Many were considered for the position, but Princess Twilight asked for you personally..."
Gleaming was already glaring and opened her mouth, ready to endlessly protest yet another nepotistic attempt from her family until the Princess cut her off. "Yes, it is favoritism, but in these sorts of situations, it is traditional for the Princess to hoof pick a guard, so it's supposed to be favoritism."
Gleaming shut her mouth, though the glare remained intact.
"Moving on," Celestia continued, "this visitor will be arriving in Ponyville tomorrow afternoon. You are expected in Ponyville by this evening in order to coordinate with the Princess and prepare for the arrival of your new charge. This will be your assignment until the visitor departs for home, understood?"
"Yes your Majesty!" Gleaming barked automatically with a crisp salute, trying to ignore the obvious sound of restrained princessly giggles.
"Good." Princess Celestia said, after managing to swallow her mirth. "I expect great things from you Gleaming...Corporal Shield. Now, a chariot will be waiting for you this afternoon. You are given leave until then to prepare anything you might need for the trip."
Gleaming nodded, a mixture of anxiety and anticipation washing over her at the realization that this would be her first assignment of true importance. "Permission to ask a question about the assignment your Majesty?"
"Of course dear." Princess Celestia responded casually.
Gleaming's eye twitched slightly but she pressed on, ignoring the familiarity that she suspected her 'aunt' would never truly forego. "Who is this visitor I'll be watching over? I'm surprised I haven't heard of their imminent arrival if it's such a high profile situation."
"Why Sunset Shimmer of course." Princess Celestia answered, a hint of mischief in her eyes.
Gleaming's jaw hit the floor, her air of forced decorum fizzling away rapidly. "Sunset Shimmer? The criminal who attempted to steal Twilight's tiara?"
"Well, former criminal," Princess Celestia confirmed with a slight nod. "One of your sister's first acts as a princess was to issue her a full pardon."
"And I have to protect her?" Gleaming's voice dripped with quiet venom. She had heard bits and pieces of Sunset Shimmer's supposed reformation from Twilight, but it had mostly failed to dissuade her overprotective tendencies towards her sister.
"Protect her yes, but also protect Equestria from her, should it be necessary." Celestia once again stepped around from behind her desk. "That being said, try not to judge a book by it's villainous past, Sunset once held a place at my side not unlike Twilight's." She wrapped her wings around the slender guard, ignoring her protesting expression. "Now you take care of yourself, and watch over your sister, I'm not sure what I would do without either of you."
"Yes ma'am..." Gleaming muttered grumpily, enjoying the hug despite herself.
~~~~~~~~~~~~~~~~~~~~~~~
The day had turned into a fast paced blur after her meeting with the Princess, and Gleaming soon found herself on a chariot rapidly approaching the small town of Ponyville.
"Corporal Shield, ma'am, please hold on, we'll be making our descent in the next few minutes," one of the pegasi called back from the front of the chariot. Gleaming nodded and pressed herself tight into her seat. While technically a part of the guard, Gleaming had never met any of the Royal Chariot Team before, as they typically trained with the Wonderbolts rather than the main body of the guard.
True to their word, moments later the pegasi angled themselves downward, locking their wings out to their sides, and the chariot rapidly made it's way earthward. Outwardly, Gleaming projected a look of calm focus befitting her occupation, but inside she was struggling to hold onto her lunch. Despite being a unicorn, she had the same love of having her hooves on solid ground that most earth ponies did.
Acrophobia notwithstanding, it wasn't long before Gleaming was stepping out of the chariot with only slightly trembling hooves. Just as she turned back to the chariot to levitate out her luggage, she heard a familiar call.
"Gleamy!"
Gleaming's head shot right back around and an enormous grin spread from ear to ear. "Twily! I've missed you!" she cried as she practically galloped up to her little sister (who, much to her chagrin, was almost as tall as she was at this point). The two embraced for a few moments before Gleaming looked around, noticing the distinct lack of five other ponies. "Where are the girls? I haven't seen them in ages," Gleaming asked with a small frown, the slightest bit miffed that nopony else had taken the time to accompany her sister.
Twilight chuckled, noticing the familiar look on her sister's face. "Relax tough girl, they're all preparing for Sunset's arrival, they're very excited to meet her," she explained happily, before frowning at the dark look on Gleaming's face. "Hey, what's wrong?"
"I'm just not so sure I like this whole idea, I don't trust this Sunset girl, who knows what she's planning." Gleaming growled.
"Hey!" Twilight admonished sternly. "She's my friend, and practically an Element of Harmony herself at this point...and you're going to be her friend too! So commandeth the Princess of Friendship!" Twilight mock ordered in the haughty royal voice she'd been practicing in the mirror for weeks.
Gleaming's sour mood fell away in the face of Twilight's antics and she couldn't help but laugh. "Alright, alright, I'll play nice, your Majesty." Despite the fact that her little sister really was royalty at this point, it was impossible for her to say the words without heavy sarcasm.
"I knew you'd come around," Twilight said smugly. "C'mon you big softy, Spike prepared you a room in the new castle. I'll give you a quick tour and then you can get settled in."
Gleaming nodded happily and began following Twilight. She still had several misgivings, but something about seeing her sister always brightened her day, regardless of the circumstances.
~~~~~~~~~~~~~~~~~~~~~~~
The next twenty four hours had been devoted mostly to family catch up time, with very little planning for Sunset Shimmer's arrival getting done. Of course it wasn't for lack of trying. Gleaming had made several attempts to prep for what she was convinced would be an inevitable crisis, but every time she attempted to get down to the work at hand, Twilight would simply dismiss the topic.
As a result, Gleaming was in a rather foul mood as she stood beside her sister in front of the enchanted mirror through which their guest would arrive. "I can't believe this! I don't have any magic-proof shackles, haven't prepared anything but the most basic of defensive spells, and I didn't even have time to put my armor on before you dragged me here!" she whined as Twilight was carefully inspecting the mirror and the contraption attached to it.
"Oh hush," Twilight snapped. "We've been over this a million times already. She is my friend. She will be your friend. She is not a threat, and you will be nice to her." Twilight finished with a glare that said 'or else'. "She'll be here in a few minutes, so try not to look so grumpy."
Gleaming just huffed as she watched Twilight place an ornate book in the holder over the mirror. Immediately, a sheen of magic flew across the mirror's surface, and it started to ripple almost imperceptibly. Minutes passed with Twilight smiling eagerly at the mirror while Gleaming gave it a mistrustful, almost challenging stare. Finally, in a way that was almost alarmingly anti-climactic, a yellow pony sporting a long mane of alternating red and gold simply stepped out of the mirror and into the room.
While her appearance had been fairly mundane in terms of interdimensional travel, the pony still looked somewhat disoriented, her eyes rolling slowly before finally coming to focus on Twilight. "Twilight! It's so good to see you!" she squealed before barreling towards Equestria's newest princess. Just as she reared up on her hind legs in order to wrap Twilight in a hug, she was suddenly catapulted sideways by a blue and white blur.
"I knew you couldn't be trusted!" Gleaming roared, pinning Sunset to the library floor. "Twilight, quick, help me hold her down!"
For her part, Sunset wasn't struggling at all. She just found herself staring up at her assailant, eyes wide with confusion.
Twilight sighed heavily, a hoof pressed to the bridge of her muzzle as she began to regret choosing her big sister for this particular job.
Author's Note
So I came up with this idea after reading a comment claiming nobody ever shipped Sunset with anyone but Twilight, so special thanks to fimfiction user Shogoki for the inspiration. Well that and I really wanted to use Gleaming Shield for something, because she's adorable and considerably more fun to write than Shining Armor.
Hopefully any of you who are fans of Principal of Equestria still enjoy this slight indulgence. I probably should have spent my time working on that instead of this, but I've been having a bit of writer's block and this story just sort of fell out of my head and onto a page. Updates for this will be random at best as Principal of Equestria is still my primary focus, but it is a fun divergence now and then so who knows.
Also, definitely on the lookout for cover art if any of you artsy folk feel like helping me out, somehow there's no art of Gleaming Shield and Sunset Shimmer together out there, believe it or not 
