A small silver filly was on her bed, watching out her window, waiting for the thunderstorm to go away, so she could see her favorite part of the sky. The moon. "I can't believe it's raining at night! Nopony loves the moon like I do..." She flopped onto her bed. "I can't see the moon again tonight...Too bad nopony can do anything to help..." She had soon fallen asleep, wishing she could see the moon tonight.
Silver Shine woke up, wishing she had seen the moon. "Just another day of insults and boredom...Wish I could sleep trough it and wake at night..." She got out of bed and got ready, heading towards her school. The bright morning Baltimare sky was incredible, but not like at night. At night, there were stars, the moon, and usually no rain. Usually. When Silver Shine arrived at school, most of the ponies laughed at her and called her names like "Hopeless", "Blank flank", "Silver Shot", and some even called her "Moon Lover". The last one didn't bother her. She did love the moon. The sun had nothing on it to her. She picked up a rock and threw it at another Pegasus who called her Hopeless. "Shut up!" She turned away and walked to her classroom. Silver Shine had to sit through her classes, wishing she could just do it all at night, and sleep trough the sun. When recess came, Silver Shine simply waited under a bench on the playground, not wanting to be made fun of anymore. She hid so nopony could see her. Recess ended, signaling only an hour and a half left in the school day.
She left once school was over and ran home to do her homework so se could visit the only place she knew ponies wouldn't make fun of her. She knew it was the school's after hours parties she could be there at. She loved the music, and she never needed to talk to anypony. It was perfect for her. She quickly did her homework, ad in perfection, too, and put her things away. "Only an hour left until I can go...I should head to work until then." She couldn't stand having to live alone, but she pushed it all aside and headed quickly to her job, weather inspection. She arrived at where the weather crew was and followed them to where they could see all the clouds. "No." Silver Shine said. "The clouds should be shifted a little south, and shouldn't have rain or snow. Just lightning." They flew back down and she handed them each five bits. "Sorry...I need what else I have."
She rushed to her school and entered calmly. As she entered, she heard the sound if live musicians performing in the cafeteria, but she went to her classroom. It was where she could hear everything before deciding where to go. After a few minute of close listening, with nothing but music and conversation, she decided to head to the cafeteria. On her way out, a stallion Pegasus bumped into her. "Sorry, little filly. I was looking away."
"It's fine...I was just on my way out."
"Did ya just read a book?"
"No, sir. But I was doing something in there that I do all the time."
"There's a book I know of about a true story. About Nightmare Moon, but not just ancient past events, it also has what happened to the users of the Elements of Harmony."
"Really? Is it here?"
"Sure is! Want me to grab it?"
"S-Sure."
The stallion walked past her and looked on the shelves until he found a book and gave it to Silver. Silver took it and sat down, reading the title. "Nightmare Moon's legend? Is this actually real?"
"It's as real as the pages."
Silver Shine opened the book and began reading. Not much was seen that she didn't learn in history class for a while, until she hit the present. She read about how each of the six ponies represented an Element of Harmony, and stopped Nightmare Moon. What got her attention most, though, was that there was some energy left that flew away from Luna, able to communicate with ponies. He put the book away and walked home, enjoying the moonlit sky. "The stars...So pretty..."
She got home an ran to her room so that she could sit in bed and look at the night sky. Before she got into bed, a voice called something to her. "Silver Shine, correct? Tell me, do you like the night?" Silver Shine dove under her bed and replied, "Y-Yes...I love the night. Why? Who is this?"
"I am somepony who was thought defeated long ago. I can't tell you why just yet, however. Please, close your eyes."
Silver Shine closed her eyes and almost opened them when she saw Nightmare Moon in front of her. "You're what was separated from Princess Luna, aren't you?"
"Indeed. Please tell me, though. Would you like an endless night?"
"You...You can't really do that...Can you?"
"I take it you would enjoy it then?"
"Y-Yeah. I...Sure would!"
"There is something you need to do to help me return. There are three keys hidden in three castles in Equestria, and when brought together in my castle can bring me back. But not normally. I would be free from Luna. A separate pony."
Silver Shine got into bed and kept he eyes shut. "I can do that...I'll find them once I can get the chance..." She fell asleep before hearing if Nightmare Moon had more to say. When she woke up, she found a gem with magical essence, and she knew she would need it someday.
--18 Months Later--
Silver Shine finally found the key at the old castle, and flew up. She accidentally threw it trying to look around, so she used the gem from that day to create a dark mist to use to locate the key...
Author's Note
How was it? I think this reveal on her backstory could make things more understandable. There's more to be added later, but it contains spoilers. Once Equestria's Fate bits that part, it'll be near.