The following is a fan-written story. Naruto is owned by Kishimoto Masashi, yada yada yada yada...
I'd say "Please support the official release", but Naruto is over and I refuse to acknowledge the existence of an alleged sequel about a hypothetical son which shall remain unnamed.
Takeo was the first one to find her by the side of the road, sitting on an odd brown pack that looked almost as big as she was. She was chewing on some kind of ration bar, and looking in the complete opposite direction of the caravan's approach. He considered the possibility she was a distraction for an attack, but decided it was unlikely. This close to the border, there was no shortage of patrols to intercept bandits or missing nin, and a large clearing like this was a horrible place for an ambush.
Still, he remained hidden in the nearby trees and studied her. She had straight brown hair, cut in a face-framing chin-length bob. She was pretty enough, he supposed, with fair skin and brown eyes. She wore sturdy-looking brown boots, and there was a kind of eccentric practicality to the rest of her clothing. The trousers and long-sleeve buttoned shirt certainly looked made to last and good for travel, materially, but the random splotching of black, brown, and green that covered them seemed ridiculous. If it was supposed to be camouflaging, Takeo had doubts about its effectiveness. Some kind of rigid brown pouch was fixed to her left thigh, clearly a weapon holster of some kind, though just what kind of weapon it was supposed to hold, or even how the pouch opened, escaped him. The long black construct leaning against her leg was just as alien to him, beyond his instincts insisting it was also a weapon of some sort.
She tensed as the sounds of the caravan finally reached them, grabbing for the black object at her side before she registered what the noise was, and relaxed. He did as well, having tensed himself in the event he'd misread the situation, but it seemed she was simply a lone traveler. Which had its own issues, honestly – this woman was either very brave or very foolish to be traveling alone, even in this time of relative peace.
Briefly, he wondered if she might be from the Land of Lightning. There were always rumors of Kumo getting up to strange research (when they weren't trying to commit bloodline theft), and new technology from the region was particularly coveted by R&D. He brushed the thought off. No, if he had to guess a country of origin for her, he'd have to say it was the Land of Fire. The markings on her cheeks in particular seemed vaguely familiar, though the memory slipped away from him every time he tried to pin it down.
The brief flare of Tarō-sensei's chakra (and he would always be Tarō-sensei, no matter how long ago their genin days were) brought Takeo back to the present. He flared his own in response, an implied 'all-clear'. The woman didn't react at all. That, coupled with the lack of chakra he sensed from her, convinced him she was a civilian.
He remained in the tree and watched as the caravan came into view, the woman hurriedly stuffing the wrapper in a cargo pocket and slinging the black device across her front as she stood up. Daisuke appeared at his shoulder, and after a few hand signals moved off ahead of the convoy to take over his position as scout. Takeo remained behind for additional security, as Tamura-san, the caravan director, and – yeah, that was Tarō-sensei's shadow clone – approached the woman.
Her name was Ohara Erin, and she was very, very lost. Her speech was mildly amusing: an odd mish-mash of overly formal and child-like, like she'd only learned to speak late in life and there were quite a few words she still didn't know. Neither she nor Tamura-san seemed to recognize any of the places the other listed off, and the story she told about how she got here was too ridiculous to be believable. It only further convinced Takeo she was harmless – no self-respecting infiltrator would try a cover so outrageous. She just woke up on the coast a couple days east, with no memory of how she got there? Please. From the look on her face, she knew how unbelievable it sounded too, but he had to admire how she stuck to it. The odd make of her gear and strange symbols she insisted were words certainly lent credence to the idea she was a foreigner, but Takeo still couldn't shake the thought he'd seen her somewhere before.
Tarō-sensei's clone eventually concluded she wasn't a threat, and left the final say up to Tamura-san. Ohara-san volunteered to do odd jobs or serve as a guard in return for letting her travel with them, which somewhat put the decision back in Tarō-sensei's hands (to Takeo's amusement). After some haggling, they agreed she could join the caravan at least as far as Yugakure at which point, Tarō-sensei readily admitted, it wouldn't be Cell Four's problem anymore. Ohara-san actually laughed aloud at that.
Ohara-san quickly proved her capability, as a general helper if nothing else. Unloading, loading, setting up, serving food… if an extra hand would be helpful, she could usually be found nearby. Some of the civilian women frowned at her odd dress and tutted about her indulgence in manual labor, but those were mostly the short-term travelers, people traveling with the caravan for safety's sake or convenience, and it didn't seem to bother her in the slightest. She struck up a fast friendship with one of the caravan's semi-regular members, a cabbage merchant named Ujie Akii. Ujie-san signed on to the caravan every three or four months to make her deliveries (and was absolutely not a cover for their old teammate Akiko, which he needs to remember before he nearly blows it, Daisuke), taking advantage of the hotels and restaurants that were taking advantage of the travelers who came to visit the many natural hot springs. The two seemed to bond over being the "weird unmarried working women", as Ujie-san put it, and the "lessons" she gave the new girl to "make you sound like less of a country bumpkin."
(Takeo knew he slept easier knowing Akiko was on hand if Ohara-san turned out to be a threat, and suspected the others did too.)
Ohara-san, for her part, picked up the lessons with a speed that seemed to surprise even her, which brought another theory to mind: brain damage. Tarō-sensei admitted it was a possibility when Takeo mentioned it, but cautioned they had no way of knowing unless they could convince her to come back to Konoha with them, which might itself not be a good idea. He kept the feeling he knew her from somewhere around the village to himself until he could recall the clan her markings reminded him of. They were nearly to Yugakure by this point and Ohara-san seemed perfectly content to stay with the caravan, which was continuing north into the Land of Lightning, so it was probably a moot point. Didn't stop the thought from bugging the shit out of him, of course. Ohara-san was providing much more colorful commentary by this point, and Takeo knew it was Akiko talking, not Ujie-san, when she said she was going to miss the strange girl's sense of humor, dry and dark as it might have been.
When they did arrive at Yugakure, Ohara-san took the odd step of actually shaking Cell Four's hands and thanking them "for everything" (whatever that meant) before jogging back over to help Tamura-san and the other workers unload the caravan's current cargo. Takeo quickly put it out of his mind; with their "official" mission over, the whole Cell met up secretly for one last touching of bases before they moved to camp outside the city and waited to provide backup that hopefully wasn't needed. Takeo didn't know about the others, but he certainly had plenty to think about while they were cooling their heels. You'd think it'd be easier to recall which clan had rectangular purple face markings, even if it was a minor one.