Sasuke cursed himself for not noticing the signs earlier. His opinion of fangirls was so low that he had overlooked obvious signs in the favour of sticking to his initial opinion of her being an annoying fangirl. He barely glanced at Sayu otherwise.

Now that he knew, he let himself take a good, long look. Looking at her gave away a lot; her clothes were very revealing. Her abdomen was toned, she wasn't overly muscular for a teen girl, her muscle was lean and attractive. He guessed that she had to be attractive, for she was probably one of those kunoichi who seduced men. Sasuke had never understood how men can be so stupid as to get distracted by their opponent's body, but it didn't matter, it worked.

"Like what you see?" She batted her eyelashes again, leaning towards him. Sasuke shook his head dazedly and walked towards the exit. Sayu followed, skipping alongside him merrily.
"You're a kunoichi." There was no question about it. She nodded slightly, looking at him with a newfound curiosity. She probably thought she could fool him for longer.

Sasuke initially planned to head to the training grounds to do some light training, he didn't want to go back to his dingy apartment, but it wouldn't be so bad if Sayu decided to follow him there too. If she was as competent of a kunoichi as he thought she was, he didn't understand why she was so clingy towards him (then again, she was related to Anko). He planned to find out.
"Ne, Sasuke-kun-" Hell no. F*ck if he was going to allow another round of 'sAsUkE-kUn'.
"Just call me Sasuke." Sayu blinked in confusion, but obliged. He felt mildly irritated by telling her to call him just by his first name, potentially giving her the illusion that they were already that close.

"Hm, Sasuke, where are we going?"
"I am going to the training grounds. The better question is why you are following me." Sayu giggled girlishly, moving closer to him. Her hips swayed sensually as she walked. Sasuke was unaffected. It was annoying how she kept trying.

"I want to get to know you better." Sasuke rolled his eyes. There was only one kunoichi pathetic enough to be skilled, but infatuated with a boy at first sight, and she wasn't here.
"Stop spouting shit," He commanded. Sayu made a fake hurt noise. She said nothing. That meant he wouldn't get his answer.

They were at Training Ground 7. Sasuke gave Sayu no warning before he attacked her with a high kick. She dodged flawlessly, moving to strike Sasuke in the solar plexus. He parried, twisting to the side to avoid her roundhouse kick. It was a feint, and she had nearly got him. For an hour, they sparred. Sasuke had to admit that he was going at full strength.

They only stopped when both of them were panting, their muscles aching. Sayu collapsed, laying in the grass and basking in the sun, followed by Sasuke.

"You didn't give me a warning," she whined. Sasuke rolled his eyes.
"As if you needed one."
That was frightening. In terms of taijutsu, they were even. Sayu managed to match an S-rank ninja in taijutsu. Maybe she was weak in other aspects, because he certainly hadn't heard of her. Someone with S-rank capabilities would've certainly been recorded in history books, right?

That's when the realisation hit him; the history books weren't entirely accurate, probably covered up on purpose. It would be easy for an enemy ninja to acquire another village's history books, so maybe it was stupid of him to not realise their inaccuracy. If Sayu was a spy, or an assassin, her existence couldn't be recorded, or it might cause another dispute between villages.

"Well, Sayu could tell the Hokage about his skill level. Now, he had an inkling as to why she followed him. Pretending to like him was an act, and bumping into him was on purpose. She knew exactly how to annoy him, yet stay close to spy on him.

"Last one there is a rotten egg!" Oh no. Why couldn't the ground just swallow him up? It was Obito. And the other flurry of footsteps told him that the rest of Team Minato was there. What perfect timing. Now Obito and Rin could pester him about his new 'girlfriend' and Sayu would giggle annoyingly and latch onto him.

Obito was closer than he thought, because the kid leaned down and stuck his face annoyingly close to Sasuke's and yelled, "Oh, hi Sasuke! What are you doing here?" Then he spotted Sayu and yelped again, his face coloured a furious pink. Rin, Kakashi and Minato appeared like flies.
"Oh, Sasuke-san! I didn't know you had a girlfriend."

He grunted, getting up, "I don't." Minato seemed to question this, analysing his unwanted companion to pick out any lies. Or maybe he was secretly a pervert.
"Not yet!" God, she was annoying. Almost as annoying as Karin and Sakura put together, except she wasn't actually in love with him.

"We keep running into each other, don't we?" Minato said this conversationally, but Sasuke didn't overlook the hint of suspicion in his voice. He grunted in reply. Minato smiled at Sayu politely. She smiled back, all signs of her previous fervor and flirtatiousness gone.

They both looked horrid. From the previous incident, some of the blood wasn't theirs, but because of their spar, they were covered head to toe in scrapes and bruises.
"Sasuke-san, kunoichi-san, would you let me heal you?" Rin piped up, "I've been training as a medical ninja!" Sasuke nodded reluctantly. It wouldn't be good if any wound got infected.

Rin ran her chakra-coated hands up and down Sayu's body. Her skin magically patched itself up. Sayu thanked Rin, blabbing to her about medical ninjutsu. Sasuke noted that Sayu had a bit of experience as a medical ninja. She finally left after that, grinning and winking at Sasuke.

Once Rin had finished with him, he thanked her and was about to leave, when Obito started jumping up and down in front of him excitedly. He wanted something.
"Sasuke! Teach me something! Please." His eyes were pleading, his bottom lip stuck out in what he thought was a cute way. There was something about the kid that tugged at Sasuke's non-existent heartstrings.

Sasuke leaned down to eye-level with the kid and spoke softer than he thought capable, "Shouldn't the clan teach you?" Now the kid looked like he was gonna burst into tears. Sasuke inferred that, due to Obito's differences, the clan didn't like him much. But the kid sure was determined, and it could be interesting, if nothing else, to teach him a few things.

He looked to Minato and his team for permission. The guy hesitantly nodded. Rin grinned, glad for her teammate, and Kakashi was as stoic as ever. It was unsettling to see the guy so gloomy, but Sasuke got the feeling that Kakashi was always like that, he just found another way to express it.

Sasuke trudged away, motioning for Obito to follow him. He could feel the kid's exuberance. Once at a suitable, far away spot, Sasuke decided to test his abilities first, starting with a light taijutsu spar. Well, it was light for him, since he recently exerted himself, but Obito was clearly hard-pressed to keep up.

His moves lacked speed and coordination most of all. First, he'd work on speed.
"Obito," the kid paid rapt attention, "don't try to hit me. Just dodge." Then, Sasuke struck, moving at a speed just slightly faster than Obito, meaning the kid had to try a little extra hard. He ran out of breath after 10 minutes, which was actually quite impressive.

"Take a break. You have two minutes." Upon saying that, Obito collapsed, panting heavily. He got up again soon after. Sasuke repeated the exercise, observing that Obito held out for a little longer each time. The kid improved quickly, just like an Uchiha should. He was more Uchiha-like than he thought.

After an hour, Sasuke began going through basic Uchiha kata, finding him quite lacking, but working to fix it. To be honest, he only knew so much himself, since he only went off the textbooks in the Uchiha's library and had no practical teacher. He found himself strangely hopeful for Obito. There was no way he'd allow one of his own to be weak and ridiculed by others.

In the future, Obito either got killed by Itachi or died before that somehow. Whatever the cause, Sasuke swore to never let a single Uchiha die during a massacre.

He didn't realise that he had activated his Sharingan. Obito was transfixed.
"Wow, it's so pretty! I've never seen a Sharingan like that," he remarked, but then frowned. Sasuke immediately caught himself and turned it off, but it was too late. Obito had seen the Eternal Mangekyou Sharingan.

"Sasuke, is that...the Mangekyou Sharingan?"