Cedric remembered when Sofia first came to stay with the royal family. She felt so isolated from all her friends, so distant from everything she knew all her life. She felt trapped in this huge drafty castle. Alone and bored. Then she met Mr Cedric, and suddenly she had a friend, someone to talk to about anything. Together, they went on fantastic adventures, and he filled her world with magic. He played her villian, her best friend, her sole confidant. He saw parts of her she didn't dare to show to anyone else.
She grew confident and lovely. The princess who was once so terribly lonely was now surrounded by friends and loved ones. He watched from the window of his tower as she walked through the royal garden with princes who would gladly have her for their future queen. Every so often, she glanced up to make sure he was still there. Little by little, their time together lessened, and Cedric knew the day was coming soon where she wouldn't need him any more.
He heard her bound up the stairs to the dusty old tower. He greeted her at the door, looking drawn and pale. She set about cleaning the workshop, chatting to him about everything she did before her visit that day.
"Oh, Mr Cedric. I wish you could have been there!" Sofia told him, and he forced a sad smile. He hadn't been able to leave the tower with her for such a very long time. This was the place where their connection was strongest, and as time went on, his reach shortened until he only existed within these walls. When it was time for her to return to her royal duties, he waved goodbye weakly, knowing he wouldn't be seeing the princess again.
"Farewell, Sofia. You have grown up to be a wonderful young woman." Cedric labored to say these words. A single tear rolled down the princess's cheek.
"And you have been the best imaginary friend a lonesome girl could ever ask for. Goodbye, Mr Cedric." With that, Sofia closed the tower door for the last time.
Prompt: You are a child's imaginary friend. (S)he's growing up, and you're fading away.