She knew that simply staring at his office door wasn't going to accomplish anything, but even so, Radiant looked very hesitant to go any further. The Crystal Guards standing watch on either side, while looking as if they wanted to ask what was wrong, nevertheless remained silent, as if worried that speaking up was only going to make things worse. But, in time, Radiant let out a long sigh, leading to a determined expression upon her face. Raising a hoof, she gently knocked upon the door, and after waiting for a few moments, an answer finally came from the other side.

"...Enter."

Radiant pushed the door open, and once on the other side, closed it behind her. As usual, her husband’s office was well-kept, with his various furniture and paperwork all neatly organised and categorized, as one would hope of a Prime Minister. The sun shone brightly through the nearby window, giving off a pleasant glittering from all of the crystalline walls and items within the room. But, Radiant's full attention was on Sombra himself, clad as usual in his blue cloak. The stallion was not looking at her, and instead, he stood away from his desk, staring at the wall behind it. Upon said wall was, unmistakably, a map of the known world, showing the Crystal Empire, Equestria an all other lands known to ponykind. Sombra stared at it intently, with Radiant watching him in silence, until the latter, at last, cleared her throat, gaining his attention.

"Oh! Radiant! I wasn't expecting you."

The mare smiled, taking a few steps closer to her beloved.

"Yes, well...I thought I'd pop in, see how you were doing."

Sombra's smile faded at that, and he glanced once more at the map on the wall. Radiant, seeing this, started to look worried, and began circling around the desk, before standing beside him.

"Is...is everything alright?"

There was silence as her response for a time, until Sombra closed his eyes, sighing deeply, before turning and pointing over to is desk. Upon it, Radiant saw an open scroll, with a great deal of writing on it. Curious, she walked closer to the desk, and soon began reading the scroll. It wasn't long before she too seemed concerned, and turned once more to her husband.

"The Griffons...are pushing into Bugbear territory?"

Sombra nodded, pointing to the North-East section of the map.

"Centuries ago, that entire swathe of land was theirs, until the Bugbears migrated down and pushed them back, bit by bit. Now, with the help of the Lunars, the Griffons are taking it back."

His eyes narrowed.

"Villages and fortifications, long-since abandoned, now have the Griffonstone flag flying above them once more."

Radiant considered that, looking from Sombra, to the scroll and back again, before putting the latter down and taking her spot beside her husband yet again.

"Well...that's not so bad, is it? I mean...it was their land...albeit a very long time ago."

Sombra gave a grim nod.

"Perhaps...but Celestia is worried. She's seeing it as needlessly aggressive expansion. And besides..."

Again, he pointed to the map.

"...with the Lunar Kingdom to the West, and Lunar-backed Griffons to the East...Equestria is looking pretty surrounded right now."

There was a seriousness to his voice that Radiant did not like in the slightest, and yet, it was hardly something she could fault him on. But, before she had a chance to say anything, she saw the stallion's grey horn light up, gaining her interest.

"What are you doing?" she asked.

Sombra, staring at the Western part of the map, narrowed his eyes slightly.

"Updating."

While confused at first, Radiant soon noticed the map itself lighting up with her husband's magic. And within moments, the words "Undiscovered West" were magically replaced with "Lunar Kingdom". When the change was done, Sombra exhaled deeply, turning once more to the scroll on his desk.

"Every other week, Griffonstone receives fresh supplies, building materials and other equipment from Queen Moon's lands...with a fresh soldier escort of course. But how?"

He raised a hoof, placing it upon his chin as he appeared deep in thought.

"How do they do it? Do they take it through the dangerous Southern territories, through Centaur lands or the Badlands perhaps? Do they transport it via the North? If so, how do our scouts not notice?"

Radiant considered that.

"Well...maybe they take it West? Maybe their land just goes on a ways and it just loops around and meets back up with Griffonstone that way?"

Sombra turned to her, concerned.

"If it did, then their territory is far larger than we ever gave it credit for."

Radiant, as before, tried considering other options.

"Maybe...maybe they're just being direct, taking this stuff straight across Equestria?"

Sombra thought on that.

"Soldiers and supplies, going right over Celestia's head...just to show they can."

He let out a dry chuckle.

"Yeah...that does sound like something the Queen would do, if only to rub it in her sister's face."

Another silence fell between the couple for a time, during which, Radiant looked as though she couldn't quite decide how to speak to Sombra, or what could be done to alleviate these concerns he was having. But she didn't even get the chance anyway, as he soon broke the silence himself.

"Princess Amore, she...she keeps saying that Queen Moo...that Luna won't do anything. She doesn't believe the two sides will come to blows, even though all of this is happening."

Radiant raised an eyebrow.

"You think our Princess is wrong?"

Raising a hoof, Sombra started massaging his temples.

"She was friends with both Luna and Celestia back in the day. And friends...rarely think the worst of each other. But me? I'm...I'm not so sure."

Radiant nodded briefly, before taking on a more worried look.

"You know...I've noticed a few...odd thing about your administering of the city lately."

Sombra didn't look to her, instead keeping his eyes squarely on the map, prompting her to continue.

"You've asked the Guard Captains to lead extra drills and practise. You've increased the number of scouting missions around our borders. I hear you've even asked how much it would take to build a wall around the whole city."

At last, Sombra looked to her, his expression one even more worried than hers was.

"I just...need to make sure we're prepared if the worst should come to it. I..."

He looked back to the map.

"...I need to do what I can."

Hearing that, realisation struck Radiant, and she solemnly nodded for a moment before speaking in a softer tone.

"So...that's what this is all about."

She stepped closer to him, sadness in her eyes.

"After all this time...you still don't think you've done enough."

Slowly, Sombra’s hanged his head, looking ashamed.

"...I swore I would do everything in my power to help the Crystal Empire. To...to do what was right for them. To...make up."

Radiant drew nearer, gently placing her hoof upon his shoulder.

"Sombra...you're not the stallion you once were. Nopony in the world has done more than you have to wipe clean the sins of his past."

Gradually, the stallion looked to her.

"I was a monster, Radiant. A cruel, angry beast. If it wasn't for you, if you hadn't...hadn't talked me out of it, I...I..."

But Radiant smiled, moving to him and embracing him in a hug, which he soon returned, before she spoke gently in his ear.

"You're not that creature anymore. The darkness in your heart no longer holds sway over you, and neither do those who sought to use you to their own ends."

In spite of everything, a smile came to Sombra's lips.

"Well...spending centuries within the healing magic of the Crystal Heart will do that."

The two shared a laugh together over that, and when they parted, Radiant gave her lover a knowing smirk.

"You weren't in there alone, remember?”

Sombra chuckled again, nodding.

"I might have been in a deep sleep...but even so...the thought of not having you with me within that slumber...I shudder to think."

Radiant nodded, placing her hoof upon the side of his face, looking at him lovingly.

"You might have been driven mad with corrupted dark magic, but don't think for a second that that was going to be enough to get rid of me."

Again, the lovers laughed, and when it died down, Sombra sighed, looking back to the map. Specifically, he looked to the Northern section, to where the Crystal Empire was located.

"I've spent so much of my life living for this city and its people...all I do...I do for them, if only to make myself better than I was."

Radiant nodded, drawing her husband's face to look at her again.

"And nopony here would ever say that you haven't lived up to that vow. But today..."

She leaned in, giving him a tender kiss upon his lips.

"...today...don't be the stallion trying to make up for the past. Don't be the Prime minister of the Crystal Empire. Simply be Sombra...my Sombra. The stallion I fell in love with."

To words such as that, what could any stallion do, but smile?

"You're right, Radiant."

He held her close, the two lovers looking relaxed and content in each other's embrace.

"The world can wait. Today...is for us."

Author's Notes:

Just to confirm, yes, that map is indeed the geography that I will be working with from now on in this story. The one real exception is that the Everfree Forest (along with the ruins), shown in the map to be more-or-less South of Ponyville, is instead immediately on it’s west, and that the forested lands in-between that and the “Undiscovered West” is all Lunar Territory. In addition, the “centaur lands” that I mentioned here are the mountainous region just West of the Badlands (depicted in the map as having that big skull on it, which the future of this story will not have of course).