Obsession of an Older Sister.

(You are Princess Luna.)

You are Princess Luna, the younger sister of Princess Celestia. Your older sister was the ruler of Equestria and controlled the sun. It was thanks to her that the sun rose in Equestria every morning. At first, everything was fine. You and your sister ruled together. She was responsible for the day, and you, in turn, controlled the night and the ponies' dreams.

But at some point, you began to envy Celestia, feeling that ponies loved her more than you. In short, you always lived in your older sister's shadow. Anger grew within you and completely consumed you, and you transformed into Nightmare Moon, your dark side. You wanted Equestria to reign eternal night, but Celestia, using the Elements of Harmony, defeated you and banished you to the moon.

After your banishment, Celestia seemed to lose a part of herself. She loved you very much, perhaps even more than just her little sister. She missed you terribly. After your banishment, Celestia also began to control the night. A 1,000 years passed after your banishment, and a few weeks ago, at the Summer Sun Celebration, you were freed because the Elements of Harmony weakened, freeing you.

You were even more enraged than before and tried to create eternal night again, just like you had a 1,000 years ago, but you were stopped by the Mane Six, a group of six ponies, friends of one of them, Twilight Sparkle, Celestia's apprentice. After your defeat, you were freed, and all your anger and fury vanished. You became your old self, and Celestia and the other ponies of Equestria forgave you.

At first glance, everything seemed to have returned to normal. You were once again in control of the night and the ponies' dreams, but Celestia became possessive, thinking that something could happen to you again at any moment. She couldn't allow that. You ignored your older sister's strange personal activities and simply assumed she was worried about you, and that it was nothing out of the ordinary.

At some point, you woke up. At first, you didn't realize where you were. Then you realized you were in a room similar to one in Canterlot Castle. Only it had no windows, and the wooden door that should have led to the castle hallway was closed. You tried using magic, but nothing worked. It was as if your magic had vanished.

At some point, you heard footsteps approaching the room, and then the small window in the door opened, revealing Celestia's face. Upon seeing her, you immediately began asking what was wrong. Celestia responded with a soft, calm smile, which seemed inappropriate in this situation.

"Don't worry, sister. I just thought it would be best if I left you here. No one knows about this room, so no one will find you. I just don't think you need to communicate with anyone but me."