Luna was holding up well on the walk to the library, though Twilight could read the strain on her face. She didn't really know how to behave. what was expected of her? What should she do? Should she treat Luna like a fillyfriend? That didn't even answer any questions, given that Twilight had the dating experience of a particularly socially inept rock.
"Twilight? What's going through your mind?" Luna asked. Twilight realized she had been staring.
"Ah, uh...I'm sorry. I'm just nervous. I don't know what to do, I mean, about...us?" the term seemed so foreign, so odd to apply. Luna both blushed and smiled, equal parts embarrassed and elated. At least Twilight knew she wasn't alone.
"You needn't worry. All you've done, and still you want to do more." she leaned over as they walked and nuzzled the side of Twilight's neck, playing with her mane. Twilight nickered, ticklish.
"There is generosity, but there is sacrifice. For my sake, please, do not go too far."
"I...promise." Twilight said with a nod. Luna was satisfied with that. They reached the library, and once again they both stopped to soak in the comfort of the place. This time they ended by turning to each other with a shared laugh. Luna headed over to her table - there was a lot of tax law to go through. Twilight decided to clear a little corner to pull out one of her books. She glanced over, finding Luna already engrossed in her studies. Twilight gathered herself. Even with the aid of Luna's bonds with the night, Twilight had done no meager amount of magic. Yet she found her limits growing by leaps and bounds. She knew the magic that came from the bonds of friendship (from what Luna had helped her learn, it was one of the most natural sources of magical energy), and wondered if with new bonds came new power. Either way, despite the spells she had already cast, she had no trouble winking out. The spell seemed to actually come more naturally - perhaps she was gaining familiarity with the magics involved. She found herself in the plane again. Everything felt more real now. She could almost claim to have a form - she could at the least better mark the boundary where her self ended and the rest of the plane began, though it still felt like these were blurry concepts for the world. Casting out her mind, she found the books, just as she had hoped. It only now occurred to her that she couldn't make out the books enough to distinguish one from the other. She grabbed one at random and winked back.
"What did you do?" Luna greeted her. Twilight blinked. Luna was staring straight at her, wide-eyed.
"You disappeared, but I could still sense you. Only barely...if your magics weren't so similar to mine, I might not have at all."
"Was I gone long?"
Luna shook her head. "Ten minutes perhaps."
Twilight sighed. "To me it was just a few seconds. I, I have this spell, I don't know how I found it, where I essentially teleport. Only it looks like actually move through this...other space."
"Magic seems solid, and what's solid more like magic. I found it out accidentally, but I can go there, even store things." she floated up the book. It turned out she had grabbed the small black book. Probably it wouldn't be helpful, but she could at least figure that out quickly.
"That's..I've done that with night before. But what space could you have found? I've never come across such a thing with another pony."
Twilight could only shrug her shoulders. "I've never tried bringing another pony there, not exactly. For now, it's convenient." she placed the book down. Luna nodded, though she gave a worried glance at Twilight before returning to her books. Twilight opened the book to its one and only page. Immediately she frowned.
"Luna? Do you recognize this book?" she asked, holding it up again to Luna. Luna looked up, blinked, and shook her head.
"No, should I?"
"It's...got your name in it. It only has your name in it." she opened it up, and sure enough, the one word on the page, in flowery letters, very simply read 'Luna'. Luna stared at it much longer than it took to read.
"I...no. I've never seen..." she shook her head and rubbed her temples. "Maybe it something I forgot? I can't...let me try something." she gestured for the book. Twilight floated it over, and Luna took it between her hooves, pressing it closed firmly. She took a breath and focused on the book. Her horn sparkled with magic. There was a brief flash of darkness (an odd experience, though Twilight admitted to herself it was preferable to a flash of light) and Luna let go of the book. It spilled open - and kept going. Page after page came out of nowhere, falling to one side or the other of the book, forcing it to grow apart on the table. It grew thicker and thicker, not stopping until it had easily three hundred pages or more, opened about halfway in. Twilight's jaw dropped and she rushed to Luna.
"It is mine. That...I used that trick to hide things from Celly as fillies. I think. But...I can't actually remember when I used it on a book."
"What is it?" Twilight asked. She glanced to the page but caught herself. "Ah, sorry.."
Luna shook her head. "Go ahead, I'm as curious as you."
'Celly was so mean today!' the book told them in flowing letters. 'I worked so hard on my golem. "Where's it's wings?" she asked. "Where's it's horn? What makes it special?". I tried to explain how its magic was inside. How it would be stronger, sturdier, and more reliable than her golems. "That's just like you, Luna." she laughed at me! "Hiding things away. It was a cute try, little sis." Little sis! I'm not a filly anymore. But I'll show her. She'll come around. Celly's just being Celly."
"It's a diary." Luna and Twilight realized together. Luna's brow furrowed.
"These are my words....why don't I remember any of this? I knew my memories were hazy, but this....why can't I remember this?"
"What happens when you try to think back to before Nightmare moon?"
"I...hnn..." Luna closed her eyes and put both hooves on her head. She shuddered and bit her lip.
"N-no. No I won't cry anymore."
"The nightmares." Luna said, unwrapping her hooves and putting them on the table. "I try not to think...I just see the nightmares."
Every day, every minute, every second as Nightmare Moon, I was living a nightmare. Trapped in the moon, I don't know. I think I shut down, let Nightmare Moon just have me. If I fought back, that was when the nightmares happened. I wouldn't have survived otherwise."
"I, I never knew! Did you tell Celestia?"
Luna shook her head slowly. "And burden her? Make her feel guilty for what she had to do? No." she shuddered. "T-Twilight, could you please..."
She need not say more- Twilight wrapped her arms around Luna tightly. She didn't let go until Luna stopped shivering. In the meantime, however, her mind turned. This mere passage brought up a half dozen questions to mind. It was hard to imagine that once upon a time, Celestia and Luna hadn't gotten along. Or at least so it seemed. She could never imagine Princess Celestia laughing at her sister. Then again, perhaps a thousand years rule wizened one a little. Twilight kept her tongue until she felt Luna calm. She felt selfish for how good it felt to be there for her.
"I'm sorry." Luna sounded like a scolded filly.
"You're getting stronger." Twilight told her. She saw Luna smile, uplifted by the remark. They turned back to the book.
"What's a golem, do you remember?"
Luna furrowed her brow. "It sounds so familiar. Golems are...were... they're important. Somehow."
"Hold on, I'm going to check something." Twilight told her. She winked away. Luna could only stand and wait for a couple minutes, keeping an anxious gaze on Twilight's spot. The young magician popped back in only five minutes later.
"No, quicker than last time." Luna told her. She could see the gears turn in Twilight's head.
"Hmm. I'm getting used to it." Twilight said, more to herself than to Luna. She had two books with her. Glancing at their titles, Twilight brought over 'On the magic of Alicorns'.
"Where did you get that?" Luna asked, impressed by the book's apparent age. Twilight cringed.
"Funny story about that. I...I may have....well, teleportation kinda makes every door look open."
Luna extended her wing to embrace Twilight. "I understand. I would hardly expect anything so mundane to stop you when you have a goal in mind."
"Right. Mundane." Twilight replied. Luna just laughed at her. Gathering herself, Twilight pushed aside books to make a gap for the tome of magic. She turned to the index, Luna reading right along.
"Golems....Golems...here we are. Only one page, huh." Twilight flipped to the noted page. It was in a chapter concerning the original elements - Earth, Sky, and Heaven. There was just one paragraph near the bottom of the page. Twilight read it aloud.
"A golem is a construct of the elements, usually based in earth, ordered by Alicorn binding magic (see page 264) and animation magic (page 83). Golems were used by the Alicorns Celestia and Luna to help in their construction of Equestria, and were never seen after the spread of ponykind, unnecessary past the construction of the land."
Finished, she turned around to Luna. The princess was deep in thought, and looked absolutely upset with the book.
"No, that's not right." Luna shook her head. "We didn't 'make' Equestria. I still remember them."
"The first alicorns. Earth, Sky and Heaven."
"There were other alicorns?" Twilight asked, hopeful but still surprised. Princess Celestia had never mentioned anything about other alicorns, though Twilight was sure there had to be something. Yes, the sun princess had never spoken much about her past at all, but Equestria was rife with creation stories (Celestia didn't like 'spoiling' things, she once claimed) but not a one mentioned three alicorns.
"They made Equestria. You can guess by their names. They made it..." she squinted, "...and they left us."
"I don't know. I remember them, but whenever I think of Celestia and I as a filly, I only see...us."
"That must have gotten lonely." Twilight said. Luna's head snapped erect, her eyes wide and pupils small.
"Lonely." she murmured, staring into nothingness.
"Luna? Luna, are you okay?" Getting no reaction, Twilight waved her hoof in front of Luna's face. Still getting nothing, she began to check Luna's temperature. That was when Luna grabbed her by the shoulders, face almost frightening in glee.
"I remember!" she practically yelled.
"That's...great!" Twilight said, mixing excitement with a bit of fear at Luna's expression. Fortunately the princess let her go.
"We were so lonely. We didn't know why we had been left. So we made the golems."
"Yes?" Twilight egged her on. Luna scratched her head, but continued.
"Celly made...it was like a unicorn. She had me gather stardust and mix it with mud and wind. We were so excited when we told it to move a rock and it moved it."
"The golems were like ponies?"
"Y-yes." Luna replied, sounding none too sure. "Yes. I made one like an earth pony, that's what that entry was about. We did use them for things, that was right. They were like dolls. The book was right - you told a golem what to do and they did it. I wish I could remember more."
"This is still great, Luna. Maybe more of your diary would help you remember." she began to levitate the book towards Luna, but Luna blocked it with a hoof.
"Read it with me." she said. "I may need your help understanding."
"Are you sure?"
Luna giggled and nuzzled Twilight for a few seconds. "You've seen deep inside me. If you haven't mocked me yet, I doubt my ravings as an unwise filly will change that."
"I don't know." Twilight teased. "You sound pretty silly."
"Twilight!" Luna's face dropped. She sniffled. "I, I thought...."
"Ahh, Luna, no, I meant-" Twilight stopped as Luna dropped the act and began giggling madly. Twilight smiled, but Luna continued giggling. It was infectious, and before Twilight knew it her lips were quivering. The two ponies leaned on one another for support as they laughed for several minutes straight. As they calmed down, Twilight stuck her head under Luna's chin, finding another giggle in her as Luna's mane tickled her nose. She nuzzled once and removed herself from Luna.
"Alright. Alright. We should get to work."
"I love you."
It caught Twilight off guard. They had said it before in the heat of the moment, with their emotions laid bare. But now here they were in a library at who knew what hour. And the feeling was none the less for it.
"I love you too. Now let's get to work."