After a long, long moment of contemplation, Luna finally opened her mouth to speak.
"Surely, sister. Somewhere out there. There must be." Luna insisted.
"There isn't. You know there isn't." Celestia said calmly.
"The mountains, in the Frozen North. The mountain that the seaponies lived under. Help us think, Sister." Luna continued.
"I've flown out there." Celestia reminded. "We both have. Miles and miles in every direction. Days on end."
"Even we can't hope to have scoped out all of Equestria." Luna pointed out, turning to her sister and snorting derisively. "And what of lands beyond? Surely, surely, there must be an island still remaining. A beautiful, tropical, palm tree and conch shell-laden island."
Celestia sighed. "Luna..."
"The Everfree." Luna said in sudden epiphany. "Nothing short of complete decimation could destroy the Everfree. Why, with how long it's been, we wouldn't be surprised if we go there right now, and find the trees have grown up to breach the water. Land would follow next. Then, within just a few years, unclaimed tropical paradise."
"We've checked, Luna. Many times. The Everfree is dead." Celestia reminded gently.
"The Everfree can't be dead. It was here when we first came to Equestria, for Celestia's sake."
"It's dead." Celestia spoke finally, frowning. "By my sake or anyone else's. I'm sorry, Luna. There are no more islands. There won't be for millions of years, I'm sure. It's more likely the sea shrinks than for new islands to form."
Luna didn't respond to that one.
The two of them stood on the roof of Canterlot Castle, the sole remaining spire that was now their home towering behind them. Luna ruffled her feathers unhappily as they watched the ocean.
Their's was the last remaining speck of land in the infinite ocean.
"Strewth." Luna said.
"I know, sister." Celestia agreed.
"We always said. Didn't we always say? Once Twilight took over, we'd go on our adventures for a few more decades, and then it was the island life."
"I know, sister."
"We even had one picked out. Out in the sea named after us." Luna seemed to get briefly sidetracked. "Did you know they named a sea after us?"
"They didn't name a sea after you, Luna. I named a sea after you." Celestia gently reminded.
Luna turned in confusion. "Verily? When would this have been?"
"A few centuries after your banishment. When people had begun to forget there was a Luna. It was symbolic."
"Oh. Many thanks."
"Of course."
Luna thought for a moment.
"Could you name this sea after me?"
Celestia sighed. "Of course. Right now, in fact. We'll make it official. The one in front of us is the New Luna Sea."
"Yes. And the one behind us is the Tiberius Sea."
Celestia blinked, and turned to her sister.
"...I don't get a sea?"
"We're out of sea." Luna said simply.
"The entire planet is covered in water, sister." Celestia said snippily. "Where we stand now on Canterlot Castle is all that remains which is not sea. I would like it very much if I could get a sea."
"You can have Canterlot Castle. Call it Celestia Island now."
Celestia kicked the hard roof under them. "I don't want to call it that. It would be disrespectful to the ponies who built it."
"Who are we impressing, sister?"
"And anyway, it's not an island."
"Well, there are no other blasted islands, are there? Yes, we decree it, right now, this is our Tropical Island. And we will spend our retirement here, just as we planned."
"You chose that, did you now? Over living in the ocean?"
"We could live in the ocean. Theoretically." Luna pointed out.
"We wouldn't be able to breathe."
"We wouldn't be able to drown, either, sister."
"It doesn't sound very pleasant."
"We could get used to it. In theory. But we're not going to. We're staying right here, on Celestia Island, between the New Luna Sea and the Tiberius Sea, and we're going to stay here and relax, drinking ale and listening to ballads, until a new civilization arises around us we may then join."
"And rule?"
"Nay. We are retired, Sister. Being princesses is behind us."
"Very well. That sounds like a plan, then."
"We certainly can't think of anything better."
"So."
"Right."
"We should probably get started."
Celestia nodded. "We can take sandbags from one of the rooms above the water. Slit them with our horns, make us a beach."
"We need palm trees. Beach balls."
"Alcohol."
"If we swim deep enough, we may be able to reach the liquor supplies. All of the bottles lent to us by dignitaries, which we've been storing. They've been water-cooled."
"Yes."
"And the ballads?"
"We can sing."
"I cannot sing, Sister."
"We, WE can sing. And besides that, my royal hindquarters, you can't sing."
"Not royal anymore."
Luna shook her head. "You are a pony, are you not? You can sing."
"I can't sing, sister."
"You've never tried." Luna accused.
"I've tried. I've tried near well everything, of course I've tried to sing before. When we sang together, I always let you take vocal lead." Celestia calmly refuted.
"I don't believe you. I just don't believe you."
"You don't?"
"We don't. We don't believe you. Strewth." Luna cursed her slip-up.
"I thought so."
"We are getting off-topic. The ballads."
"Yes. I'll listen to you sing, Sister."
"Then we shall drink together, and make merry."
"Although neither of us can get drunk."
"Nay? We could have sworn it's happened before."
"Cadance could get drunk. Twilight could get drunk. We cannot."
"It would have made some things easier."
"Very."
...
"Then that's our plan?"
"So it shall be. So we decree, as sole remaining citizens of this land."
"Let us get to work, then."
The two sisters stood on the roof, continuing to watch the sea churn and sway for miles in every direction.
Neither of them moved.
"As soon as you're ready, sister." Celestia prompted.
"Well, it doesn't have to be right now. Again we ask, who are we impressing? We surely have a few million years before the ocean recedes. And even then, for multicellular life to form again..."
"Sister, the Seaponies are probably having a ball right now. Don't act like Equestria has been reduced to liopleurodons again."
"Is that really what we want, sister? Verily? For us to be the sole remaining creatures on the planet with lungs, while society and evolution moves back to gills and blowholes?"
"Creatures with blowholes have lungs, sister. Whales. Dolphins. Whaleponies. Dolphinponies."
"You miss the point. What I intend to say is that we can take our time. Who's waiting on us?"
"I am, sister." Celestia gently reminded. "It's hot, and humid, and even the sea breeze can't change that. If anybody in the history of Equestria has ever needed a good cider more than I do right now, I may eat them."
"This is the island life, sister."
"This is the two old fools standing on a rooftop, waiting for the seas to bend to their whims life. I won't have any of it, nor will I glamourize it."
"Is that all we are now, sister? Old fools? The great Celestia and Luna, to become the great Ozymandias?"
"You said we wouldn't be princesses anymore, Luna. Nor rulers of any title."
"They made tapestries of us." Luna said bitterly. "Statues. Paintings. Named cities and towns after us. All underwater now. That lovely statue of us in the Gardens, growing barnacles as we speak. Are we to be two old ladies, standing on a roof now?"
"Bickering about the way things used to be in our day, yes." Celestia confirmed.
Luna snorted. "Well, they were better when we were fillies."
"Less water."
"There was less water, aye."
"It's not all bad, sister."
"Nay?"
"No remaining terrestrial life on the planet means no expectations. No day or night court. No tea tasting. No diplomatic visits. We have all the time in the world, quite literally."
"If we did not raise the sun or moon for days, nobody would notice."
"And the oceans would boil."
"Err. Yes. But we just mean, hypothetically."
"Indeed." Celestia flicked her tail.
Luna looked thoughtful. "The dream realm has been empty. We've never seen it quite like it is now. If we travel for long enough, we can still find dreams, of course. The dreams of whales, or octopi. But no creature quite as intelligent as ourselves."
Celestia didn't respond.
"We've searched. We spent all night searching, chose a direction and flew. It used to be a galaxy in and of itself. Now it's just... Liquideous. Black. Darkness in all directions, floating in nothingness. There are few left who still can dream. If the seaponies do indeed live still, we have not found them."
Luna tittered.
"I struggle to remember what it looked like before. Soon it will be a distant recollection, with no mental image attached to it. And still we will be here, standing on this roof, waiting."
...
"There is paint, sister."
"Hm?" Luna flicked an ear.
"In the tower behind us. The one which has not been submerged. It just occurred to me. They stored materials from that play I was in, for... archival, I suppose. Anything I've been in contact with is usually squirreled away somewhere."
"Aye. Remember that flea market?"
Celestia smiled. "I couldn't even say with complete certainty whether I had or had not come into contact with the items the seller claimed I had. It would have been so long ago. Many of my earliest centuries are a blur."
"Yes."
"I imagine my time as Princess will one day be a blur, too."
"The paint, sister." Luna reminded.
"Yes. Right. If we could retrieve it, we could paint on the tower. The floor. Any remaining part. Make our own island."
"And then what would we do?"
"What you said, Luna. Enjoy some relaxation. Music. Alcohol. All of it."
"For how long?"
"Until we grew bored."
"And then?"
"You wanted this, sister. You wanted a tropical island, that is what I intend to give you."
"It was never the island, sister. It was..." Luna struggled for words. "It was what the island represented. It was symbolic. Exactly what you described. A break from responsibilities, from ponies, in which we could close our eyes for two moments and not have to battle some ancient evil. We can't get drunk. We can't sing. What could we do with a beach ball, sister? Play for a few minutes before we got bored? Before our horns popped the blasted thing? And palm trees. They're just a set piece. Coconut water. I've tried coconuts. We've tried distant ancestors of coconuts. Coconuts have been around in some form or another for over 5000 years, and they've never tasted good. Honestly, we will not miss them. If we could undo this, refreeze all the frozen land which has melted, sink the oceans, revive every species which is now extinct? We would leave coconuts to their demise. We never want to see another coconut for as long as we live."
When Luna was finished speaking, Celestia gave her a moment to catch her breath. The waves beat against the walls of their tower, mischievously licking spots of water at their hooves like a cat's tongue.
"We apologize, sister."
"You're quite alright, Luna."
"Still. We should not have lost control like that."
"It happens to the best of us, sister."
Luna looked away, shielding her embarrassment, before exhaling subtly.
"Come to think of it, sister, there really is no reason to use the royal We anymore."
"Was there ever?"
"It was symbolic, sister. You know this. 'We' meant myself, and the nation we spoke for. Our words were the words of the common pony, and we only ever did that which would better our species and our country."
"Very true." Celestia nodded sagely.
"But there's really no need for that anymore." Luna straightened up. "We speak for ourselves. There is nobody else left to speak for."
"I suppose."
"Now then. About our plan. You said the paint was in the tower, sister? The top floor?"
"Yes, it is. The remnants of that play I was in."
"I recall. It was very memorable."
"Hush. We could fly up there with ease, duck in through the window, retrieve the cans and brushes and set to work right away. Do you wish to fetch it?"
Luna closed her eyes.
In her mind's eye, she pictured what she would do with that paint, given the chance.
It would be crude, of course. Luna never claimed to be an artist. But Celestia would recognize what it was well enough.
Blue skies, little white specks that must have been seagulls. Crabs and shells dotting the beach, the sand that tapered to a point on the horizon and vanished. The beginnings of a green forest filled with palm trees, growing ripe coconuts beneath their leaves. Chairs and sand castles implying the presence of other beachgoers, although none were in use.
Nay- They would be in use. She would paint ponies, hundreds of them, dotting the beach like they used to. They would not swarm her or her sister, begging for photos and autographs; They would simply enjoy a lovely beach day, just like their princesses were doing.
No. Empty beach. No other signs of intelligent life, not even chairs or sand castles. Only the crabs and gulls, and distant dolphins dancing out far from shore. A true paradise, where the two of them could close their eyes and hear only the other's breathing, and the cool wind of the sea.
Luna's mural would cover the entire the spire's entire outer wall, wrapping around like wallpaper. Sand would be poured out of bags to cover the cold brick ceiling, and a chilly six-pack of ciders on the ledge would overlook the ocean.
When her sister would arrive, Luna would silently levitate up a discarded collapsing chair, un-collapsing it and setting it down behind the cider ledge. Another for her own usage, and she would take a seat, looking expectantly at Celestia.
Celestia would lift a bottle of cider from the box and join Luna, kicking back and taking a well-deserved vacation.
Their retirement would finally, truly begin.
No more islands.
No more beach balls. No more sand castles. No more palm trees. No more coconuts
For a while, anyway.
Clinking bottles, the two alicorns would sip back cider as they patiently waited for the New Luna Sea to recede.
Wasting away on Celestia Island. Just the two of them.
For millennia.
Luna opened her eyes again, looking thoughtful. A smile slowly came over her.
"Yes. Yes, we should begin work."
"Indeed. As soon as you are ready, sister." Celestia nodded.
"As soon as we are ready."
"We will begin, and we will make our tropical island."
"Verily. A tropical island to spend our days on."
"That would be lovely."
"We would drink coconut water and listen to the ballads on guitar."
"Watch the ocean."
"Yes."
"Indeed."
The two sisters continued to watch the sea.
Neither of them moved.
