She concentrated, as she had done so for so many years. Concentrated and focused her power, using all her magic to move the celestial body before her. Celestia stood on the balcony of the highest tower of the palace of Canterlot, performing a ritual and duty she had been bound to for as long as she could remember. The setting of the sun.
The sky began to dim as the fiery orb descended upon the horizon. Within moments, it was gone, and the land of Equestria was now deprived of it's light and warmth. There was a time when that would be the end of Celestia's daily duties, but these days, there was one final task she had to perform. Turning around, she now faced the east.
Closing her eyes once more, her horn began to glow again as she focused her power into moving yet another important part of the world. Slowly, the pale white orb rose above the eastern horizon until it hung gracefully in the night sky. What followed was a swarm of tiny dots of light which surrounded the orb and the blackness around it.
The moon and the stars.
Celestia opened her eyes and gazed upon the sky before her. It was beautiful to be sure, but looking upon it never brought her joy. Only sorrow and a crushing sense of loneliness.
It was not always like this. There was a time when it was the duty of another to watch over the night of Equestria. Those years had been a happy time for Celestia. The days when she was not burdened with the remorse she now felt every day. The days when she was not...alone. But those days were gone now, and she had to accept it. But knowing that never made it any easier for her.
Having now finished her daily duties, the princess of Equestria turned from the sky and made her way back inside the castle. Once inside, she was accompanied by two of her armour-clad pegasi guards. They did not speak to her as they wandered down the halls, for her face spoke volumes, and it told them that she wanted no conversation this night.
After a few minutes, they arrived at their destination, a large wooden door trimmed with gold. The entrance to Celestia's bedchamber. The two guards took their respective positions on either side as Celestia passed through the doors. Once inside she closed the door behind her and went about her usual rituals, including the removal of her royal jewellery. Her golden crown, necklace and horse-shoes.
Celestia made her way to her bed, a massive purple cushion adjacent to the large and ornately designed gold-trimmed windows. She began to lie down on the cushion, relieved to finally have some comfort to enjoy today. But before she laid down her head to sleep, a look of melancholy appeared on her face. She looked up through the window to the moon, which practically filled her view from her chamber.
In particular, her gaze was fixed upon the distinctive mark on the moon's face. An image of a unicorn head, which all ponies throughout Equestria had become accustomed to seeing upon the moon's face. But while most ponies simply accepted it as part of the moon's appearance, Celestia knew better. She knew fully well what that mark meant, and it broke her heart every night to have to see it.
She let out a deep sigh.
"How many time must I do this to myself?.....To her?"
Gazing out on the moon again, Celestia slowly closed her eyes as her horn was once more enveloped in the golden glow of her powerful magic. A few moments passed before the princess opened her eyes again, and when she did, she did not see the interior of her bedchamber.
Instead, it was, from her perspective, as though she were mere metres above the surface of the moon. This was a spell she had learned long ago. To transport not her body, but her mind to other places. She could in theory send her consciousness to anywhere, but these days, she only chose this magic to send her mind to one place and one place only.
Closing her eyes again, she cast her mind even further afield. And when she opened her eyes, all there was, was an endless darkness, a place where light could not dwell. Her mind was now within the moon. To an outsider, it would have looked as though Celestia was a dim candle-light in a dark room. But she could not allow herself to dwell on her grim surrounding. For there was somepony very dear to her which she had to see.
As she had done for so many nights now, she flew deeper within the darkness. As the moments passed, nothing could be seen. But Celestia had made this journey many times now and she knew where she was going. And sure enough, she soon found her place. For there, hovering motionless before her, was the very pony she'd sought to find here.
It was an alicorn, like her. But with a fur as dark as her curerent surroundings. The mare was clad in blue armour that threatened danger, and her many flowed just as elegantly as Celestia's, but with the colours of the night sky rather than the distinctive rainbow hues of Celestia.
It pained the sun princess to look upon this creature. She knew what she was supposed to look like, what she was supposed to feel like. And this was not it.
The dark creature stirred. It was obvious that she knew Celestia was there, and even more obvious that it was ignoring her. Celestia approached with caution. She knew it was dangerous for her to be here, but she didn't care. She just had to see her, however painful it was for her to do so.
This mare had been so close to her not so long ago. She was family. Her whole world. And now here she was. Bound for her crimes. Twisted. Corrupted into something she was never meant to be. Loneliness, resentment and isolation had embittered her into being this...thing. This...nightmare.
And deep down, Celestia knew that she bore part of the blame for this. She knew deep down that something had been bothering her. She knew something was wrong. But she never took the steps to try and fix things. She never even asked. Even though it had never been her wish for strife to emerge between the two, she now stood here, regretting her indecision every single night.
"Luna...can you hear me?" She asked quietly.
The creature before her did not respond. It merely kept it's large wings folded in front of itself as though trying to hide from the princess. Celestia knew how angry she was at her, but approached closer nonetheless.
"I've just finished the night sky. It hasn't had the same level of style that yours once bore. But I have done as well as I could. I hope you can see it one day."
Celestia knew that small talk was pointless here. The prisoner was not paying attention. But talking to her like this was all she could do to try and make the situation bearable, even though such an attempt failed to do so. The dark mare's silence merely served to make the princess feel even more miserable.
"Luna....please....speak to me."
Her voice was wobbling as her sorrow began to wash over her. There was nothing she wanted more in the entire world than to embrace the broken mare in front of her. To turn back the clock to the days when the two of them could be in each other's company and just be...happy. To be a family again is what her heart of hearts screamed out for, even though her head knew it could never be.
But then, to Celestia's surprise and hope, the mare began to speak, although softly.
As Celestia stepped further forward, she was taken aback by a jolt of purple magic which struck at her from the dark mare.
Celestia's shock was evident, but she did not strike back. Instead she merely dodged the attack and turned her attention back to the mare who had once been her sister.
"Luna....I know you're in there somewhere."
The dark mare said nothing. She merely floated there, wings now unfurled, and observed the sun princess. Celestia's eyes were saddened, almost pleading. But the dark one could not give her what she wanted, nor would she give it to her if she could. She merely stewed in her own resentment. Her anger over her imprisonment. To be deprived of her land, her people, her precious night sky. It was all too much to bear.
Celestia spoke again.
"Can't you....can't you come back? Please come back to me Luna."
That was the final straw. The former ruler of the moon rose up, wings stretched out, and howled at the white mare.
"IT'S NOT FAIR!!!" She screamed.
Much to the dark mare's surprise, Celestia's face appeared out of nowhere mere inches from hers. Her expression lost all of it's anger, replaced by surprise, and even sadness. The two said nothing, merely looking into each other's eyes. They knew what they wanted to say to each other, but also knew that doing so would accomplish nothing. At the end of the day, no matter what was said here, Luna was still a prisoner, and Celestia would walk the earth alone.
Eventually, Celestia turned from her sister and began to float away, leading to the latter folding her wings in front of herself once more. Celestia gave her one final look before departing.
"Until tomorrow night........Luna."
Celestia allowed her magic to fade. The dark world around her vanished, replaced by her bedchamber. With her mind now back within her body, Celestia merely placed her head gently on her pillow and closed her eyes, trying to get to sleep.
And as she did, a single tear fell down her cheek, a symbol of her pain over her loss of her beloved sister.