The Doctor stood in the balcony doorway, looking out at the familiar figure in front of him. She was leaning on the railing, looking out at the city below. The sky was a dark blue, like Earth's just after sunset, and the Doctor could see only her dark silhouette. Regardless, he knew exactly who it was.
"Hello." The Doctor said, walking up beside her and looking down at the city himself. It looked a bit like a dark blue ocean, covered in small white pinpricks of light streaming out of people's windows.
"Hello, Sweetie." River Song said, as normal. The Doctor looked down at her hands and saw that she was holding a silver pocket watch, flipping it over an over almost absentmindedly, though the Doctor could tell she was giving the watch quite a bit of thought, as she kept glancing down at it at regular intervals.
"That watch-" The Doctor said hesitantly, then sighed. "Can I see?" River handed the watch over without a word, still looking down at the city below. The Doctor himself still only trusted her for the sole reason that she gave the very first time he met her, despite the number of adventures they'd had; he was beginning to suspect that the only reason why he'd tell her his name was because he'd already told her - a paradox. Bringing himself out of his thoughts, he looked down at the watch in his hands, and felt his stomach drop at the familiar symbols etched into the side.
"I know. This may be the first time you've seen it for you, but it's not for me. I know what it is, and I don't want it." She said, still not looking at him, taking the watch back and putting it into her pocket protectively.
"River. Maybe you don't understand what this means." He said shortly.
"Or maybe you don't understand what this means for me. I like my life, and I know you well. I don't want to remember the War. I don't want the burden you have. I've always been at least a little lonely, but I don't want what I see in your eyes, every day."
"But I- we won't be alone." The Doctor said quietly. When he got no reply, he began to get angry. "So you'll help me deal with the burden, but you won't share it? You'll be here to support me, but you you won't do it when you have a chance to really make a difference?" River sighed, as if she'd been expecting this; knowing her, she probably had.
"It won't make that much of a difference, and you know it. Besides, by the end of the War, what had they become? What will I become, if I open that? River Song will be lost."
"River Song will still be a part of you." The Doctor replied firmly.
"Oh? Just like John Smith is still a part of you?" River countered.
"The metacrisis is living proof of that." He insisted. "Besides, John Smith didn't do anything particularly extraordinary, apart from at the end. You've had almost the life of a Time Lord yourself-"
"Apart from the age and the burden and the War." River said. "I'm not opening it." The Doctor merely sighed and turned away. River's lips quirked. "Oh, and I suppose this isn't the end of this, is it?" River said, almost tauntingly.
"No. It's not." The Doctor said, turning to give her a stern look, pouring all nine-hundred years of his life into his gaze. River merely lifted her eyebrows slightly in response.
"That look in your eye is exactly why this watch will remain closed. You're constantly going on about old age being a curse; would you curse me?" She asked, knowing the answer.
"River Song, there is one single reason that I trust you. One." He looked her in the eye, a single finger raised and pointing in her direction. "Even then…" He trailed off, looking back to the city and letting his arm drop.
"Really? And what's that reason?" She asked, actually not knowing. The Doctor chuckled humourlessly, more of a scoff than an actual laugh. He turned, but before he left he said one last thing.
"Can't say. Spoilers."