You were the only surviving child of Rhaegar and Elia Martell. But not many knew about you. They thought that you died just as your twin, in the hands of the Mountain.
Yet something unexpected happened. You weren't sure how you survived, while your siblings died cruel death in hands of people supporting Robert Baratheon. But one was clear, you won't be alive for long.
Your uncle and aunt, ran away to Essos. And that was probably the smartest way of avoiding death. But you found yourself in the North.
You were taken under the wings of maester Aemon, who was a maester of the Night's Watch. But Robert's men were still killing everyone of your family, so to avoid death, he and Lord Commander decided to pretend you were a bastard man.
You grew up around mongrels and cold. You weren't really one of the Black Brothers. You were a woman after all, pretending to be man, but no one knew that and no one needed to know.
You fought like a man and your body was well hidden under the thick black coat. Your hair was never longer than to the length of your shoulders. The only problem was your voice, but Black Brothers were dumb, and mostly just joked about it, saying you had a voice of a woman. If only they knew.
A few days ago Jon Snow joined the Night's Watch. He didn't take an oath yet, but he was talented and you knew that he will soon do it. Jon also liked you, he thought you were a bastard of some important Lord, just like him, which made him notice similarities between you two. You also weren't a r*pist or a murderer, which was another plus. It wasn't a surprise you were the only person he liked.
You were just changing in your room, when you heard the door open. And you turned your head around to find Jon there. He at first didn't notice the bandage wrapped around your chest, but when he did, he furrowed his eyebrows and looked at you with a suspicious look.