Not my characters. Third story in The River Loop Trio.

...

"You gorram idiot!" a young female voice yelled.

The Time Agent hated reconnaissance missions. Never knew what he was getting into. The assignment had been to investigate the Blue Star System of the 25th Century to find out precisely why several billion human colonists to a solar system with no native alien life whatsoever managed to not only lose contact with Earth but also have a significant chunk of their history either wiped or altered.

His Vortex Manipulator automatically took him to somewhere with breathable atmosphere, adequate temperature and gravity, and with sufficient open space for him to stand, but other than that he had materialized in uncharted territory. The universal translator chip embedded in his brain worked for most languages, and he had plenty of precious metals and a psychic credit card tucked away in various places, but he had not been prepared for this.

He had been half an hour on this moon, and the young woman had been the first living being he had seen. The town he wandered through had been empty. It looked much like the Old West of 19th Century North America, except with the occasional holographic window, and had clearly been inhabited until quite recently.

He turned to see her. She was a slender, barefoot presenting-as-female individual with long black hair, a flowing, loose-bodied dress, a communication device clipped to her ear, and a crude, spiky axe in either hand.

"Oh, um, hi," he said, hoping like hell it wasn't another apocalyptic scenario, because they'd cut back on the overtime pay at the Agency.

She rolled her eyes. "Time traveler. Figures. And you haven't met me yet."

"You've met me?" These things happened occasionally to Agents; dealing with them was part of their training. "Where is everyone?"

"Evacuated on suspicion of an upcoming Reaver attack. Which happened after all, but fortunately about twenty miles off. My people managed to deal with the main group. Just sweeping for survivors. Come along."

"Why should I?"

She started walking away. "You haven't decided on the name you'll eventually have, but you're still secretly looking for Gray, and you'll remember me as the first person who promised you you'll find him."

He felt cold all over. "What...what name do you know me by?"

She stopped, spared him a glance, and her smile was like sun through clouds. "Follow me, Jack."

He ran after her, and would have run to the end of the galaxy. "What's a Reaver? A kind of alien?"

"Nope. Human that's been exposed to the Pax. It's a drug. Makes most people all peaceful and calm. Makes a very, very few into Reavers. Speaking of which..." She tensed and pointed with one of her blades.

Twelve, no, thirteen figures. Like ghouls. Howling. Spotted them. Ran towards them.

"Get down. Keep a shot for yourself, whatever you do." And she leapt -

A few minutes later, he had not even pulled the trigger once (he'd been afraid of accidentally hitting her, she was such a quicksilver dancer of a killer), and she was wiping blood out of her eyes. Her dress was stained with it. None of it was hers.

She calmly touched her com. "Got some stragglers. Is the sweep finished? Shiny. Tam out." She turned it off.

"What are you?"

"She was supposed to be a girl. Then she was supposed to be a weapon. But now she's me." She strapped the axes to her back and took his hand before he had a chance to puzzle that out. "My ship is near. You'd be asked inconvenient questions, and though the Alliance has softened it's still not kind to people who don't belong."

He followed her as she tugged him along, as if hypnotized. "I still don't understand..."

"My name's River. My ship is called Hoban."

...

It was a cozy little space hopper, meant for one or two people comfortably, four at absolute maximum. No hyperspace or warping capabilities. In the living quarters were a single bed, a lavatory unit, and a kitchenette with a fold-out table and two hand-carved benches. Through a set of silky (though heavily patched) bamboo-fiber curtains were the pilot and co-pilot seats, with several plastic dinosaurs glued to the dash.

"Not until I've washed up and we've had dinner," she said, motioning him to the co-pilot seat as she prepared for liftoff.

"What?"

She giggled. "You want to bunk with me, but you're scared of asking because of what you saw me do. Don't worry. I've been waiting for it. Ten years now"

"You're psychic."

"Yes."

...

In the morning she gave him a digital file on a large clear disc, along with a silver box for him to play the disc with. "This has the history of our civilization. Your superiors should be happy."

"I can stay longer -"

She kissed him softly. "I'll miss you, but it's time for you to go now," she said, cupping his cheek in her right hand. "Forgive the Bad Wolf. She meant well."

"I've asked you a lot of questions, and I know you can't answer them all," he said. "But just before I go, where are you going and what exact date will you land there?"

...

When River landed on Shadow, where Kaylee and Simon had settled and worked at their trades, happy and quiet, she found the man who had been Captain Jack Harkness waiting for her at the landing pad. His hair was all gray now, and his coat was brown instead of blue.

"I was wondering if you might," she said, a smile breaking across her face.

He laughed and gathered her up in his arms. "I had the date and location written in my diaries. All of them. Every one that I kept, over the centuries. I even started using the name again."

His kiss felt the same, but she allowed herself to melt into it far more. "Oh, my old, old friend. Come meet my brother and ask for my hand."