This was so wrong, this was all so horribly wrong.

Princess Luna paced her room like a madmare, ears flat, nostrils flaring, circling her room over and over again. Her wings rose every so often, giving a sharp, anxious flap, then returned to press to her back, quivering with the force of her muscle tension.

Well, there was nothing to do for it, was there? She had no other recourse.

She was going to have to run away from Canterlot.

She hadn't begun her week in a state of panic; she'd actually been very happy. A funny thing to imagine, considering all of the years she'd spent in exile. Being 'happy' was something she was not particularly used to, but it was something she'd sorely missed.

Princess Cadence's wedding had been a beautiful affair, despite a surprise attack by the Changeling Queen. She'd missed all of that, thankfully, because she just wasn't sure how she would handle another royal coup. She had made it in time for the ceremony, for the beautiful cake and flowers, the happy guests and the smiling, joyful couple. It warmed her heart to see two ponies so in love with one another. She hadn't known Cadence well, but she had immediately liked her. Kind, compassionate, warm - someone who genuinely deserved to find love.

The warm feeling from the ceremony stayed with her in the hours and days afterward, kindling a fire in her heart she had thought long-dormant. It warmed her from the inside out, as if she carried a piece of a white-hot star in her chest, glorious and bright, shining from her every pore, glimmering in her eyes when she spoke to the night-guards.

"Sister, may I speak with you?"

Just like that, the little piece of star flickered and died, and dread took its place. Celestia was smiling, but Luna did not know her so poorly as to miss the line of tension in her body, despite how she tried to hide it. Celestia did not rise during the night; she woke in the moments between nighttime and day, rising just in time to bring the sun up and end Luna's night. This was just after midnight, in the middle of Luna's rule, and she would not be awake now unless something was very, very wrong.

"Of course, Celestia." The words came out automatically, as if it were someone else speaking to her sister, someone else guiding her legs towards the large throne room.

It was only once the large, heavy doors were closed behind them - how confining those doors could feel, with their dark, unforgiving wood - that Celestia began to speak again, her voice taking its stronger 'regal' tone, as if she was making some royal proclamation. She never used to speak to Luna in that voice; once, there was no distance between them, for they were one heart beating in two bodies. How things had changed.

"Luna, as you well know, the marriage of Princess Cadence to Captain Shining Armor has been a joyful occasion for all of us. We have all been overjoyed to see their love blossom, and take shape."

Well, this wasn't as bad as she'd anticipated, Luna thought with abject relief. Probably just some official business to take care of, once Cadence was gone from the castle.

"She will be very missed by all of us, of course, because we all loved her very much. But in each of our lives, there must be change, and for some of us it comes later than others. There is a duty for all of us to fulfill, whether it be ruling the kingdom or carrying on our line, so that there will always be someone to protect our Little Ponies."

Something was wrong. Something in Celestia's gaze, the way she said it, belied the growing anxiety in her words. "I know mine duty very well, sister; hath I been lacking in it? Prithee make clear thine frustrations, and I shall remedy it." Luna spoke a little hastily, slipping back into the Old Tongue in her distress.

"No, sister, you have been carrying on your duty with great excellence." Celestia hurried to praise her - she'd always been fast to praise her, nowadays, after the Nightmare had taken over. She had changed, almost as much as Luna had. "But your duty is going to ... change."

Luna frowned, and her wings twitched on her back, wanting to rise and flap anxiously. Wing-flapping was not a princessly action, her mother had chided her; now, there was no one who dared to critique. "Change? Change - how?"

Celestia bravely tried to soldier on, but it was obvious she was losing the battle of keeping a smile on her face. "Well, in light of Princess Cadence's wedding...?" and she trailed off, hoping Luna would take up the thought. When she didn't, Princess Celestia sighed, tightened her wings, and forced herself to continue. "There has always been a royal duty for every member of our bloodline, for as many generations as we have existed. Our mother and father fulfilled their duty, as did theirs, and so on. There is a place and a job for every royal, and there is no shirking of that duty."

"And my duty is to raise the moon, as yours is to raise the sun." Luna finished, in what she hoped was an intelligent, good-student sort of way, but her smile vanished when Celestia did not return it.

"That had been our duty, for many years. But when you were banished …" Celestia trailed off, eyes softening, and Luna knew that she was remembering the many, many lonely years that her sister had suffered through. But the softness vanished, and she soldiered forward in her speech, doing her best to keep her voice even and calm. "When you were banished, I was forced to call on a power I did not know I had, to lift both the sun and the moon. It is a ceremony that every firstborn princess must undertake; I merely undertook it many years before it was necessary."

"Necessary...? Sister, what art thou saying?" Luna spoke, her voice rising, her old dialect returning.

"There are always at least two sisters, Luna; you know this as well as I do, for you have studied our royal bloodlines as far back as I have." Celestia said, struggling to keep her voice calm, but Luna could see something in her gaze, some kind of fear; why wasn't she understanding this yet? "The eldest sister is the one who must protect the kingdom from harm, and dedicate her life to its care. The younger sister-"

"Is the one who must carry on the bloodline." Luna finished her sentence, blood draining from her face, dread tightening its grip on her heart. "Thou cans't - you can't mean that! How am I supposed to - I've been gone from the royal court for a thousand years, I have no beau, no prospects, I cannot -"

"I have found a suitable stallion for you. He is of royal blood, of a good house -"

"You cannot do this!" Luna cried, and for a moment, her voice rose in volume, becoming sharp and loud; it startled her as much as it startled Celestia, and when she spoke again, it was with a carefully modulated voice, struggling to keep it low. "You cannot, sister! You cannot - marry me off to some stranger, some stallion I have never -"

"Luna, calm down. If you would only listen -"

"No! I will not - I will not have - returned from a thousand-year prison to walk into - you can't do this!" her voice rang through the tall, stone room, sharp and loud. She whirled, wings flapping as she galloped from the room, abandoning her sister as Celestia cried out her name.

The halls and stairs passed in a flurry; she had some dim awareness of where she was going, but it was only once she was back in her private chambers that she realized where she was. She kicked her door shut, slapped the lock into place, and began to pace.

This was all so wrong, this was all so horribly wrong.

Princess Luna paced her room like a madmare, ears flat, nostrils flaring, circling her room over and over again. Her wings rose every so often, giving a sharp, anxious flap, then returned to press to her back, quivering with the force of her muscle tension. There was a circle worn in the carpet, from all of the times before when she had paced. Pacing helped; pacing kept the anger at bay, kept it at the back of her mind, kept it from rising up and taking over again.

Keep calm, Luna, stay calm. You'll get through this all right. Your sister wants to marry you off to some blueblooded - stars above, was she going to be wedded to Blueblood? He was so pompous, so arrogant, so unkind, so - so -

Deep breaths, close your eyes, keep circling, think about happy things. Think about the moon on your back when you fly, think about the stars that reflect in the lakes, think about the night birds that sing you their lullabies.

Think about never seeing those things again, think about being trapped in a marriage with a stallion you despise, think about raising his selfish, spoiled children, think about looking into his eyes for the rest of your life and seeing your dreams, your beautiful night, slipping away a little more every day.

Stop that. It took a lot of deep, heaving breaths to get that last nightmare out of her mind, and when Luna had calmed her breathing and opened her eyes again, she was standing in front of her mirror, grateful that she had managed to keep any tears from falling.

She would never be able to keep the Nightmare at bay, not in that life. She could barely keep herself calm here, where she was happy; how could she do it in a nightmarish world of forced marriage? And then the Nightmare would rise again, and who knew what she might do, this time? How many ponies she might hurt? How many countries would she lay waste to, and how long her imprisonment in the moon would be this time? Would a prison on the moon be a better prison than one in Equestria?

She stared at herself in the mirror for hours, refusing to let herself cry, as her mind went over every option over and over again, trying to find some other solution. As the sun rose, marking the end of her reign, she came to one, final conclusion. There was nothing else to do for it, was there? She had no other recourse.

She was going to have to run away from Canterlot.