It would be a slight understatement to say that Diamond Tiara didn’t get much sleep that evening.
Not for once, caused by her mother’s constant commands and demands of her to act more ‘refined’ in public (in other words: stop ‘pretending’ you’re not better than everypony else. A year later, Mrs Spoiled Rich had still never quite got over Diamond’s radical shift in personality that fateful day outside the school when the older pony had been verbally eviscerated. Ouch.)
Neither was her ongoing insomnia caused by her father’s sky-high expectations involving Diamond’s future role as the sole inheritor of the entirety of Barnyard Bargains. Or her guilt over her beloved veteran butler’s declining health, no doubt exacerbated by more than a decade of demeaning tasks and unnecessary acrobatics, mostly at her behest.
Gently dabbing the many beads of sweat filtering down her brow, the pink filly resisted the life-long urge to pull the nearby cord which would promptly summon hired help. I’m gonna have to deal with many crises throughout my life, both personally and professionally. Might as well start learning to cope on my own now.
She clambered out from underneath her plush bedclothes, and trotted over to her walk-in bathroom. Once inside, she began filling up her glass with water for much-needed refreshment, as well as stare at her bloodshot expression with genuine fear that this perpetual restlessness might already be making her age prematurely long before her time.
What do I do? What do I do? The question was hardly a simple one, especially for a filly so young (regardless of how mature she was). Pushing her innermost feelings to the darkest depths of her ailing mind would appear to be the simplest option, if she hadn’t actually tried that tactic already to minimal success.
She had no idea why she felt this way. The wretched individual who kept intruding into her thoughts like an uninvited parasite was hardly one of her best friends. Or even a casual acquaintance. They’d had a single meeting in the most unpleasant of environments ages ago, and honestly it hadn’t gone so well.
Also, in analysing recent events, the rendezvous didn’t exactly achieve anything like the desired effect, either. So why, if she’s so beyond redemption and such an intrinsically wicked filly do I…
Diamond splashed some of the cold moisture intended for oral hydration upon her face and stared at her uncertain reflection some more...
...And the more she gazed in earnest, with a thousand different experiences of her own almost-capitulation to the twin vices of selfishness and corruption playing through her mind like Bad Movie Night…
... The more her initial hesitation crumbled into fragments of dust and her resolve strengthened into a mineral as hard as her namesake might suggest.
It’s gonna be difficult, some might say impossible, to even get this plan set up considering all her crimes... let alone find out if it works or not. But I’ll never know if I don’t try, not to mention the fact that my conscience won’t give me a moment’s peace until I do. So starting from tomorrow, I’m gonna talk to Daddy about everything I’ve been feeling lately, then take it from there.
“You happy now, brain? I’m gonna do everything you asked. Maybe I could… I dunno… be allowed to get a bit of shuteye now?” Diamond Tiara narrowed her eyes at her alternate self on the other side of the mirror, before taking a long swig of water and pulling out the plug.
As she watched the clear liquid within swirl clockwise down the drain and through the pipeline, she couldn’t help but think her hare-brained scheme was destined to turn out the same way.
Metaphorically speaking, of course.
My mind is made up, though. As soon as I rise with the morning sun, I’ll have three things on my agenda. One, to eat a hearty breakfast. Two, catch the early train to Canterlot. Three… to start the ball rolling on reforming Cozy Glow. For good this time.
Author's Note
I really shouldn't be starting another story, but after watching this video...
And remembering the previous one-shot I wrote along the same lines, it all just came together. It'll be a fascinating match-up between these two, and I can't wait to get started on charting their very different ideals and outlooks. With a few twists thrown in for good measure, of course. 
See you all in the next chapter... which it is out the same time as this prologue. Amazing! 
Chapter 1: Off to Canterlot Castle
“Rarity, please. It’s only my coronation in a week, not my wedding. T-That’s just a phrase by the way, don’t start spreading any strange rumours around, please. You know what those gossip rags are like.”
“ ‘Only her coronation’ she says...! Spike, could you inform your fidgety friend that this is a historic occasion, a hoofnote in time for all those lucky enough to attend. Why, years from now, ponies and other assorted creatures from nations all across Equestria will look back on this blessed day and say they were here, and how could they forget such a wonderful dress…”
“Erm, think maybe I’ll stay outta this one Rares. I might be Twilight’s chief advisor, but officially my job doesn’t start until the crown is on her royal head. Until then, think I’ll just hang around the sidelines as inconspicuously as possible: reading comics, eating gems, not pointing out that this seems a thinly-veiled attempt to drum up business for your boutique… oops.”
“Hmph! Men. What would they know about top-end fashion, or the way advertising works?” Rarity took a second to cast the sheepish dragon a withering glance, before she returned to her fitting. “It’s only fair that if I create a sartorial masterwork that gets all the glitterati swooning, I should benefit somewhat from the fruits of my labours. Wouldn’t you agree Twil… oh do hold still you silly alicorn! If you move one more inch, this bodice will tear ever-so-slightly in the middle, and then we really will be in trouble…!”
“Bodice? Top-end fashion?? Sartorial masterwork??! Whatever happened to my request for just a simple silken evening gown, Rarity?” Twilight frowned at the unicorn’s overambition, whilst doing her best impression of a motionless wax figure. “You didn’t have to go to this much trouble, surely.”
“Your request was duly considered and rejected with extreme prejudice, dear. And I do have to go the extra furlong to see you looking your best for the big day. You’ll thank me later, believe me. Now, breathe in deeply as if you’re wearing a corset: that’s good. If I staple this piece of cloth here, it should allow for the flowing effect I’m looking for as you gracefully float across the stage to accept the throne…”
A very animated Rarity went on to discuss her intricate proposition at great length, whilst Spike shot Twilight sympathetic looks from his comic book and the Princess just wanted the fitting to be over already.
Why oh why did I let her talk me into this? What’s even worse is the torture isn’t even half over yet. I’ve got dessert taste-testing with Pinkie Pie, that’ll probably escalate into a custard pie fight again. Next, I have to choose which of Applejack’s many kinds of apples I want for the main course, won’t that be a gas. Then, Fluttershy needs me to pick out specific outfits for her birdie friends, Rainbow Dash wants to demonstrate how she’ll keep the skies clear at this most ‘magical’ of events: if I’m not careful, I’ll crack long before I even become ruler. Celestia, Luna: I’m so sorry I ever thought your job was easy.
In the midst of her remorseful soliloquy, Twilight failed to spot the messenger stallion arrive in the great hall until he started speaking. “Ma’am, sorry to disturb you in the middle of your important preparations, but we have just received a special guest who has asked to speak to you regarding a matter of the utmost urgency. If this isn’t a good time, I could always get them to come back later…”
“No! S-Sorry, what I meant was, it’s fine.” Twilight breathed a sigh of relief at the prospect of a temporary escape from her prison of fabric and needles, but she didn’t want to hurt her unicorn friend’s feelings. “Apologies Rarity, but duty calls! I’ll be back as soon as I’ve dealt with our guest, in the meantime feel free to ring the bell if you need any refreshments or soforth.”
“Well, a more cooperative model would be a start, but I suppose we shouldn’t expect miracles.” Rarity wasn’t usually this brazenly snooty, but being interrupted when she was on the verge of a ‘breakthrough’ in design was enough to test her patience considerably. “Don’t mind me, dear. You go and have fun with whoever-it-is. I’ll be here, tape-measure and pins in hoof, patiently waiting your return like the good friend and true professional I am. Don’t hurry back on my account, please.”
Twilight was about to open her mouth to reassure the grumpy unicorn of her commitment to complete the process later, but Spike gently guided her away from the now empty expanse of material. “It’s okay, Twi. If I know Rarity, she’ll sulk for a little while and then take care of the stuff she couldn’t do with you around to ‘bother’ her. You know, like the frills, the lining, the extra-long train…”
“Gah! Give me a break Spike, or you may talk me into not returning at all!” Twilight would’ve facehoofed there and then, if it wasn’t so improper in the presence of one of her official messengers. “So anyway, who is this ‘special guest’ and what do they want? If it’s a friendship problem, I’m their mare! I want everycreature to know, just because I’ll hold high office in the near future, it doesn’t mean I’ll stop…”
“Actually no, Princess.” The messenger unwittingly shot down Twilight’s declaration of humbleness, to the clear amusement of a chuckling Spike. “It’s Filthy Rich, accompanied by his daughter Diamond Tiara. Usually, with such a major announcement on the horizon I’d tell them to go away, but he is a major sponsor for the festivities and he seemed quite insistent.”
Filthy Rich, what could he possibly want? He usually only has dealings with Applejack, of a business-related nature. And isn’t his filly that spoiled brat who visited my treehouse library once, and then rudely accused me of dying my tail? Although, I hear she’s been behaving a lot better of late, and even made friends with the Crusaders. In any case, what could they possibly need from me? I suppose there’s only one way to find out…
“Send them in!” Twilight summoned up all the gravitos and dignity she could muster, whilst still itching all over from the clingy dress. “Spike, you might as well stay. It’d be good practice for when you’re helping me deal with others problems on a day-to-day basis, not just when you’ve reached a boring part in your ‘Return Of The Power Ponies’ literature.”
“Oh, darn it! Just when I was about to ask for permission to… I-I mean, definitely Twi. Even if it is something as ‘fascinating’ as tax returns or opening up a new franchise, I’m sure all of us will learn something from the experience!” The sarcasm that oozed from Spike’s lips wasn’t lost on the smirking alicorn, but if she was going to suffer through this, he was going to be right by her side.
“Good, Spike. Now you’re finally starting to get it! Having responsibility isn’t just about wielding power and feeling important, a lot of it is handling matters which you’ll probably find tedious or a waste of your time. Nevertheless, they must be done. I promise it’ll be over soon: just as long as you smile a lot, look them dead in the eye and nod your head enthusiastically at the end of every sentence, they’ll never catch on that you might be less-than-interested at what they’re saying…”
“You mean… like this?” Spike then demonstrated a perfect example of the movements that Twilight had been describing.
“Excellent, Spike! Just keep that up, and you’ll get through any meetings with blustering bureaucrats with ease! Anycreature would think you’d done this sort of thing before…”
“But I have, Twi! Many times, in fact!”
“Huh? What are you talking about, Spike?”
“Well, you know how I always seemed so absorbed when listening to one of your extended Friendship Lectures?”
“Y-Yes?”
“W-Well, that might’ve been a tad misleading.”
“You mean to tell me… all this time…”
“Yep. Sorry, Twi. And while I’m in full confession mood, I taught Starlight the ‘tricks of the trade’ too.”
“...Really. It’s all starting to make sense now. I did think it was a bit bizarre that somecreature besides me could get so excited about my speculative metaphor of how friendship was like painting a fence s-l-o-w-l-y.”
“W-What are you gonna do? Send me to my room? Tell me off? I would say dock my pay, but I don’t earn anything anyway, so…”
“Spike, it’s fine. I’m just glad you told me, and as Applejack always says ‘Honesty Is The Best Policy.’ I can’t really do her accent, but you know what I mean.”
“Indeed I do.” Having already been invited, Filthy Rich stepped inside the Great Hall at this juncture, accidentally catching the end of the conversation whilst doing so. “She’s a fine mare that one, the hardest of workers and a great lineage to hoof. But in the spirit of truthfulness, I’m afraid I’m not the one who wanted to talk to you today. You see, my daughter thought if she came on her own you’d never…”
“It’s okay Daddy, I can take it from here.” A deadly serious Diamond Tiara followed her father through the big double doors a few seconds later, her steely eyes not betraying a hint of nervousness. “Princess Twilight, I know how busy your schedule must be today, so I’ll cut to the chase. It’s about the statue in the garden out back…”
Author's Note
Well, that's it for now. To see how it all turns out, please continue to tune in. I promise you won't be lacking for drama, whatever happens next. 
Chapter 2: An Audience With Twilight
“Statue?” If Twilight had been surprised at the unexpected arrival of the wealthy stallion and his young daughter, she was positively perplexed now. “Which one? We have many scattered around the gardens of Canterlot, but none of them are for sale I’m afraid. Most are hundreds of years old, and are part of the heritage of this great nation…”
“You don’t understand, Princess Twilight.” Despite her determinedly serious expression, Diamond couldn’t help but grin slightly at the thought of travelling so many miles to bid on one of those mouldy old sculptures. “We’re not here to bid for anything, or hear a history lesson. I’m talking about the one with the bad guys inside.”
“Well, that one’s definitely not available for purchase. If anycreature with evil intent got ahold of it, and was somehow able to resurrect them, the consequences could be most… oh.” Twilight’s mouth finally caught up with her brain, and she looked down apologetically. “I’m sorry. You said you didn’t want to bid on anything today, and I didn’t hear you at first. I just have my mind on so many things right now, it’s like my head is ready to explode. Perhaps it would be better if I just let you speak, and I’ll listen.”
“A-Alright.” Diamond attempted to settle her frayed nerves before continuing. She knew Twilight might be a bit jittery at her upcoming coronation, but she’d no idea the alicorn would be this burned out. “Let me give you a bit of background information first. You see, for most of my life, I haven’t exactly been the best filly. I’ve teased others for their lack of Cutie Marks, helped spread scandalous gossip around town, blackmailed others to get what I want, turned a cousin against her own family and even teased a disabled filly about her handicap. That’s just a few of the many bad things I’ve done that I can name off the top of my head.”
“Oh but my precious jewel, you’re so much better now!” Filthy Rich didn’t enjoy hearing his child badmouth herself like that, and sauntered over to gently ruffle her mane. “If only you’d told me earlier what’d been going on at home in my absence, I would’ve cancelled every one of my business trips and really told your mother off…”
“Ddaadd!! I thought you promised me on the way here, you wouldn’t interrupt me! How would you like it if I walked in on one of your important meetings, and refused to shut up?” A blushing Diamond sidestepped her father’s cloying affections upon her head, and for the first time Twilight noticed the filly was missing her trademark tiara. “You’re talking about the past, and I’m here to discuss the future. Besides, it would be nice to keep some things ‘in the family’, don’t you think?”
“O-Oh, sorry sweetheart. It’s just I hate to hear my angel criticise herself in front of the Princess, when she’s made so much progress in the last year.” Filthy Rich returned to his original standing position, to give his daughter the floor. “Please, continue. You're doing an excellent job of explaining yourself so far. I couldn’t be more proud!”
“Also, for the record, please call me plain old ‘Twilight’. I’ve never been much one for formality, and it would make me feel much more comfortable.” The lavender alicorn informed the pair of her request with a friendly smile. Wow, it looks like the rumours were true. Diamond Tiara has really blossomed since we last crossed paths. Good for her!
“If that’s what you want, ‘Twilight’. Anyway, returning to what I was saying before…” Diamond acknowledged her host’s request with a nod, before trying to get the conversation back on track. “It’s safe to say, I haven’t been the most model of citizens for most of my life. I got better eventually, as my Daddy just announced to the entire hall. But if it hadn’t been for the help of others, mostly three fillies I’m sure you know very well, I never would’ve seen the error of my ways to live a better life. And now, I have the opportunity to do the same thing the Crusaders did for me. All I ask for is that chance…”
“Wait, I’m a bit puzzled here.” Spike had mostly been silent throughout the proceedings, as engrossed as he was in an epic comic strip struggle between The Masked Matter-Horn and Mane-iac. “How did this discussion about statues turn into a confessional, followed by you offering to be some kind of mentor? I mean, this is still better than the business-related stuff I expected when I heard who was coming, but still…”
“Spike!! If you’re going to butt in without warning, at least try making your input useful!” Twilight was noticeably irritated that while her own attempts at not cutting in were going well, others in the room kept letting the side down. “I must admit though, the question did cross my mind too. Although I’m extremely proud of all you’ve accomplished and admire your laudable goal of improving the lives of others, I don’t exactly see the connection either.”
This is it. No backing out now, Diamond. “I-I was thinking about helping Cozy Glow, Twilight.”
“What?!” Well, that simple enough statement really did let the cat amongst the pigeons. Aside from Twilight’s uncontrolled yell there, Spike dropped his comic book in shock and the guards stationed nearby glanced at each other with undisguised alarm.
Even Diamond’s own father, who’d only been told by his child that she ‘needed to discuss a matter of the utmost importance’ with Princess Twilight looked gobsmacked. He’d expected the pink filly to offer to be one of the flower girls at the coronation, maybe even ask to sing as she had such a good voice.
Not… this.
Having already anticipated this kind of stunned reaction, Diamond wasted no more time in adding a few more reasons to why she felt she could succeed where a thousand court-appointed psychiatrists had failed.
“You know, I actually went up to Tartarus to see Cozy Glow once, before all visiting rights were restricted. Although, when you compare what we both did wrong in our lives, her offences are a little… worse, I think even in that short meeting I was able to kind of ‘get’ her. That lust for power, attempting to weaponise friendship for her own selfish purposes: I tried doing the same thing with my leadership Cutie Mark not so long ago. Only when I discovered my true purpose and all the good I could do with it did I ever think of changing my ways. In my opinion, right now Cozy is very muddled about what her destiny could be and how to best use her talents not just to make herself happy, but others as well. N-Naturally, she has to actually learn to care for them first, but I truly believe if I spent a lot of time with her…”
“No.”
If Twilight’s last single-word sentence had been shouted so loud the entire palace roof shook, this one was uttered with complete clarity and clear certainty. The future ruler stared Diamond’s diminutive form down to such an extent that the filly began feeling even smaller in the presence of the much taller alicorn.
“I appreciate your noble intentions coming here today Diamond Tiara, and nopony wants to reform and redeem evil beings more than me. But one brief encounter in Tartarus long ago cannot possibly prepare you for the levels of malice and manipulation this misleadingly innocent filly will throw at you. She’ll stop at nothing to achieve her goal of conquering Equestria, and if this means draining others of their magic or even killing them, I would not put it past her. We’ve heard a thousand different versions of her ‘tragic’ past, from being accidentally dropped from Cloudsdale to her parents dying in a tragic lightning storm. None of these tall tales have held up to close scrutiny, and if she can’t even be honest about who she is to us, what makes you think you can change her entire personality? Also, and I don’t want to seem rude, but you are still a mere filly yourself.”
“Now wait just a darn minute here!!” Despite his earlier vow. Filthy Rich couldn’t just stand by and allow the value of his most precious gem be called into question. Even by a Princess. “I can see why you’d be upset at my daughter springing this surprise on you at such a stressful time, and I’ll be having words later about her inappropriate conduct. But you can’t just dismiss her on account of her age! Diamond has already come with me to Barnyard Bargains for work experience, where she’s already proven herself a natural-born leader. You should see her motivate the staff as she tours the shelves with me: even the laziest of slackers ups their game considerably when she passes by issuing instructions! Why, she does such a good job the thought crossed my mind to pull her out of school to give her my foremare’s job! Naturally, that idea was quickly quashed. A foal needs their education.”
“Mr Filthy. While I can see the close bond you and your daughter clearly share, I don’t see how it pertains to helping Cozy undergo a total character reassessment.” Twilight turned her attention to the stallion, not knowing that the way she’d addressed him was unlikely to win his favour. “Besides, even if I did think there was the tiniest chance she could be reformed, there’s still the small matter of her punishment. She nearly destroyed everything Equestria stands for… twice. What am I supposed to do… set her free to come and live in your mansion? I bet you have a pool, don’t you? Wouldn’t that be true justice: a pony who almost caused the devastation of society gets to lounge in the water on an air-bed all day. Does any part of that sentence sound fair to you, Diamond?”
“Y-Yes, we have a pool. B-But…” The first signs of desperation began to show on the pink filly’s face, as she struggled to counter the salient points Twilight made. “She wouldn’t be allowed to use it, not at first anyway. You see, we have this room deep underground: a ‘bunker’, if you like. It was built as part of the mansion by my grandfather Stinkin’ Rich, or so Daddy tells me. There were a lot of earthquakes in those days, or something. Anyway, I kind of thought she could stay down there. It’s practically inescapable, but has plenty of air for her to breathe. I mean, anything’s got to be better than keeping her as a stone statue forever. Are you really telling me, there’s no chance somepony so young is incapable of getting better someday? It just seems so… c-cruel, that’s all.”
Even though Twilight maintained a stern expression, a slight pang of regret did appear in the form of an arched eyebrow. “Nopony wants to petrify another lifeform, especially one as young as Cozy Glow. And I’ll admit, when she worked with me at the School Of Friendship she did show herself to be quite the eager and efficient helper. But it was all a means to an end to gain power over us all, and that’s what makes her so dangerous. She had me and every other creature fooled, and if you want to know ‘cruel’, just ask my friend Starlight Glimmer what Cozy did to her the second I left them alone together. No, I’m sorry but any further discussion of this matter would be a waste of time for both of us. Your request is summarily denied. Please have a safe trip home, and do come back for the celebrations commencing a week from today.”
Before Twilight could trot back to Rarity’s delicate administrations however, Diamond wasn’t quite done yet. Being a master at reading body language (it helped her guide others into making the ‘right’ decision), she sensed a level of hesitancy in the alicorn’s otherwise firm refusal, and she was determined to push her further on it.
It’s not like she had many other cards to play, anyway.
“You haven’t properly answered my questions yet, Twilight. Did you think turning her to stone was the right thing to do? And, do you believe it’s impossible for her to improve in any way? If you answer ‘yes’ and ‘no’ in that order, I’ll leave this second and not come back. So, could you tell me please? I know you’ll be honest, because that’s exactly the Element you were preaching about when me and Daddy first came in…”
Diamond’s desperation had made her a bit arrogant, especially in the presence of a Princess. Again, the whole room (guards included) gaped at Twilight to see her delayed response to such ‘obstinance’...
...And her reaction was somewhat of a revelation.
“You know what, Diamond? I am starting to see what your father means when he says there’s more to you than meets the eye. Not many other creatures would dare speak to me the way you just have... and I kind of like it! Such stubborn talk helps keep me grounded, and stops me thinking I’m more important than I am. I should never forget I’m here to serve everycreature, not the other way round. So to reward you for your forthrightness: No, turning her to stone wouldn’t have been my first choice. It was Discord, together with Luna and Celestia’s help that made her petrification happen, not me. And while Cozy Glow might be one of the most hopeless cases I’ve ever encountered when it comes to reformation, I never give up on anycreature no matter how hard it may get. It’s just... I kind of reached my wit’s end with her.”
“...That’s why I think I should be allowed to give it a try! I really believe we’re not that much different, so if anypony can get through to her… wait. Did you just say, the weird guy who made it rain chocolate from the sky and turned the clouds to cotton candy decided her permanent fate?! I-I don’t know what to say to that.” Diamond was sorely tempted to say that’s nuts, but wisely decided she’d been given enough royal leeway already. “A-Anyway, that just proves my point even more! If we don’t try to help her now, we’ll never know the kind of mare she could’ve grown into if we just gave up on her! Please? Won’t you at least consider it? A fresh approach from a pony who won’t quit, her very very last chance?”
A million and one emotions flickered across Twilight’s face just then. It’s hard to describe that kind of look, unless you’ve actually seen it in the flesh.
She glanced over at Spike, who simply shrugged his shoulders and buried himself back into his comic. It was a bit early for him to start his new job, and he intended to make the most of this ‘rest’ period.
She then turned her attention to Filthy Rich, who seemed understandably flustered at the prospect of his potential new house guest. This was his daughter’s plan, he was just the chaperone. She’d grown up far too quickly for him to keep pace, and although proud as punch he was very disorientated right now.
That trait of wanting stuff without asking first? She gets that from her mother. He thought sadly, knowing that no matter how much she’d matured they’d always be a bit of Spoiled in her genes.
Still, as visibly bewildered as the tycoon was right now, it was as nothing compared to Twilight’s turbulent thoughts. And the more she pondered on everything, the more flummoxed and lost she seemed to become, until…
“I-I want some time to think. I can’t decide anything right now, and I certainly don’t believe I can do it on my own. There’s a waiting room to your left there with plenty of old magazines to read. If you want to sit inside, I’ll get back to you as soon as I can. Come, Spike. You’re going to have just as much a say in this as everypony else. I need to summon the rest of our friends, but first time for a lie-down…”
Twilight left at that juncture, still in a daze with her faithful dragon companion flapping close behind.
This left the great hall empty, apart from some very nice murals, a smattering of guards…
...And an irate father frowning at his sheepish daughter, ready to begin the mother of all interrogations.
“Well, Diamond Dazzle Tiara? What do you have to say for yourself? I’m waiting…”
Author's Note
Phew. This is the most I’ve written in one sitting for a long time, but I didn’t want to make Twilight’s decision an easy one.
After all, we are talking about releasing Cozy Glow here, so it stands to reason she’d want the input of her good friends to take such a drastic step...
….As well as make rules, establish boundaries, plan for contingencies if anything goes wrong... quite a lot to organise, in other words: and it’ll all be covered in the next chapter. 
