I am Arya Stark of Winterfell, she had said. She had those same gray eyes, and dark hair. Stark looks, and nobody doubted her. It took all Sansa's strength not to run to her, not to smother her with hugs and tears.

"We all thought you were dead! Where were you?"

Arya just smiled.

Yet, as much as she was Arya, she wasn't. She wore beautiful dresses, did embroidery and fanned herself even though it was cold. She was a perfect court lady. She wasn't Arya.

Sansa tried to talk to her. She wanted to know where Arya had been, what had she done for the past six years. Arya talked, she did, but only afterwards Sansa realized she hadn't found out anything.

She knew Arya had been in Braavos. Braavosi was a strong language, but Arya didn't have a hint of Braavosi accent. She had been gone for six years, but it sounded like she hadn't left the North for a day.

Then there where the eyes. Every time she looked at her, Sansa expected to see the familiar spark, the proud defiance that made her sister who she was. There were emotions there - happiness, sadness and even an amount of mischief, but it was all so demure. Contained.

And no spark.

There was also a harshness to her, a sharp edge that wasn't there before. It could, of course, be explained by her years of survival on her own, but it wasn't that kind of harshness. It was something else. It showed in her graceful and precise movement, in her attentiveness. Sansa was reminded of a lioness, of a predator ready to pounce. But it was all so minuscule, so unnoticeable, and Sansa tried to convince herself that she was imagining it. She was the only one who noticed. But she was the only one who really knew her sister, from before.

Sansa was scared, sometimes. She felt like there was a copy of Arya, a perfect one, but still a copy. Yet everything was so perfect now, as perfect it could be after their losses and Sansa didn't want to spoil it.

So she hid those feelings, hid the thought that there was something wrong with Arya and tried to make herself feel happy, tried to bring back the easiness of contact. Maybe it wasn't her Arya, but it was still Arya, and people change.

There was also a pinch of bitterness in her heart at times. Sansa thought she was the one that changed the most, that grew the most. She wanted Arya to be amazed by the woman Sansa became. She would've been, before, but this Arya… She only smiled demurely, almost (but not quite) indulgently.

Sansa had always been the more mature one, older and more ladylike. She had been proud of that, when they were younger, and even though those were things of childhood, it stung, if only a little, to realise how much things have changed.

Months passed, and Sansa never got used to the new Arya. Nobody noticed anything, though, so Sansa never mentioned anything, to anyone. But the suspicions were there, always clawing at her, even as she ignored them as much as she could.

So it almost didn't come as a surprise, that night.

She was on the edge of sleep, when she felt a blade at her neck. Her sister's face hovered over her, fitting with the shadows perfectly.

"Arya?" she whispered, slowly, but not really surprised.

Arya gave a minuscule shake of her head.

"Then… Who are you?"

"I am No One," the girl above her said, softly, tonelessly. Then she whispered, "Valar Morghulis."

And Sansa knew no more.

So… yeah. That's it. It's really short, but I guess that's the point.

Hope you've liked it.