"You're going, aren't you?" Celestia looked towards the distance from the opening in the wall. She sat there, the rising Sun's light streaming in and falling over her body, and despite her short mane and lack of ornaments and still injured frame she looked every bit as regal as she had in her old days.
"I have to go." Twilight stood at the foot of the wide, short staircase leading up to the elevated portion of the room where Celestia sat. "It's the only option."
"It's the only option we deem good," Celestia corrected her. "And who are we to decide what is an isn't good?"
"The only ponies who can and should make that choice, when it comes to ourselves. Not for anyone else when they don't believe in it, but this is my own battle to fight, my own decision to make." Twilight put her hoof on the stairs. "And I've already made it." She walked up and into the light, as Celestia silently waited for her.
They stood there, side by side, staring out the great natural gash in the stone wall in front of them as moment by moment the Sun rose higher in the sky. Time was of the essence, yet it didn't feel wasted as they sat there in silence. Finally, Celestia turned to Twilight. The inky mark on her bust was a black ring, with cloud-like splotches on the outer edges of it. "So soon after we last did, we have to play these roles again, then."
"Play things as they are," said Twilight in return. "You were never a good actress for the parts that didn't fit you, after all. This is just another truth, arguably a more important one, unarguably a more needed one right now."
"I don't want to lose you," Celestia said.
"Who ever wishes to lose anyone?" Twilight asked. "But you know this all better than I do. Understand it all better than I do. I'm tired of pretending I'm the wiser one. Not forever, but today. I'm tired, and you owe me this much. No sacrificing this time. No running away. Equestria needs someone and that someone will be you, if I don't make it."
"I'm tired, Twilight. Forever." Celestia slumped over, looking at the ground. "It was not supposed to be like this. I never wished for any of this." She took a deep, shaking breath. "But it's what Equestria needs." She straightened herself again, and the Sun shone in her eyes. "One more for the road, then." Her half smile quivered. "I'm sorry. But you're a good pony, Twilight. I can be proud of that, at least. I chose well."
Twilight pointed with a hoof at the black mark on Celestia's coat. "If you lose me, let me go. You've already lost too much. It's not going to be worth it."
"Equestria will need you more than it will need me."
"Equestria would rather have you than have neither of us. I know it hurts."