Naruto : Ninja school teacher, I can become stronger by teaching

Obito was a little annoyed. If Kakashi didn't participate, then his taking first place would be meaningless. What Obito wanted was to defeat Kakashi, wash away his past shame, and take first place under Rin Nohara's gaze. Without Kakashi, Obito wouldn't be too happy about taking first. His obsession with being first in the Young Ninja Tournament was entirely caused by Kakashi. Back then, in front of Rin Nohara, Kakashi had overwhelmingly taken first place with a crushing score, making Obito's championship declaration an empty boast. Obito had always remembered this, but he hadn't had the ability to win until now. Now that he had the ability to win everything, he found that his opponent had already moved on, which greatly displeased Obito.

"No way, I have to make Kakashi participate in the competition!" The more Obito thought about it, the more he felt that a competition without Kakashi was simply unacceptable.

"You can wait until after school to ask Kakashi if he's thought about participating," Rin Nohara suggested. "I can go with you. It's been a while since we've seen Kakashi anyway". Although the three of them had a good relationship, their opportunities to meet had become fewer since Kakashi graduated. She and Obito, as students, had to attend school every day, and Kakashi, as a ninja, also had missions to do.

"Okay." Obito nodded, thinking Rin Nohara's idea was good. Obito asked Muyue for a day off before school ended, deciding not to go to Muyue's place today and to resolve the Kakashi matter first.

After school, Rin Nohara and Obito went directly to Kakashi's house. Kakashi's house wasn't in the main city but in the suburbs next to it. While not as prosperous, it wasn't as crowded as the main city. Rin Nohara and Obito had been to Kakashi's house before, and had even been invited in for a meal. Seeing the large, flat-roofed house with a sloped roof come into view, they knew they had arrived. Their luck was good; Kakashi wasn't on a mission today, and when they arrived, Kakashi was training in the yard. Kakashi held a silver-white chakra short blade and, in two or three moves, cut off the head and limbs of a scarecrow. Seeing friends arrive, Kakashi exhaled softly, sheathed his chakra short blade behind his back, and asked, "Why are you here?"

"We haven't played together in a long time, and we both missed you, so we came to find you," Rin Nohara said with a smile.

Obito, however, was not as polite as Rin Nohara and asked directly, "Kakashi, the Young Ninja Tournament is about to start. Are you going to sign up?"

"Young Ninja Tournament?" Kakashi thought for a moment and realized it was a civilian competition he had participated in out of boredom when he was still in school. "No, not interested," Kakashi replied indifferently. In his opinion, that kind of competition was for kids, and the first-place prize was just a slightly more exquisite kunai. Even when he was at the ninja academy, he only participated out of boredom, let alone now.

Obito's face fell; Kakashi's refusal was too decisive. "Why? You participated before, didn't you?" Obito asked, unwilling to give up. He really wanted Kakashi to participate.

"Back then, I was still a student at the Ninja Academy. Now I'm a Chunin," Kakashi said, pointing to his ninja headband. Obito felt Kakashi was implying something; he was also a student back then, and he was still a student now...

"What's a Chunin got to do with it? There's no age limit anyway," Obito continued.

"Do I have to explicitly say I'm not interested in such a childish play-pretend competition?" Seeing Obito being persistent, Kakashi said mercilessly. Obito felt a bit heated. What play-pretend competition? It was the Young Ninja Tournament! "I'm participating too, Kakashi! You're not scared of losing to me, are you?!" An agitated Obito also started to become aggressive.

"Lose to you? Have you ever won against me?" Kakashi said with a poker face.

"I... I..." Obito frantically searched his memories and was surprised to find that he had indeed never won against Kakashi. Realizing this frustrating truth, Obito's face reddened even more.

"Don't get cocky, Kakashi! I'm not the same as before now!" Obito put his hands on his hips, indicating that he was no longer what he used to be. Kakashi scrutinized Obito. Goggles, tracksuit, a goofy smile on his face, hands on his hips—he was radiating pure silliness. Kakashi honestly said, "I don't see it".

"Leaf Village profanity!" Obito almost lost his composure.

"You two, meeting after so long and still acting the same," Rin Nohara said, covering her mouth and chuckling. This scene had played out countless times in front of Rin Nohara. Obito loved to spar with Kakashi, but it was always Obito who ended up at a disadvantage.

Obito took a deep breath, calming himself for a moment. He suddenly thought of his teacher, Muyue. "If it were Muyue-sensei, what method would he use?" Obito fell into thought. To make him train more seriously, Muyue had him do an extra problem for every hit he took. While training was difficult, doing problems was even more unbearable, so choosing the lesser of two evils, he trained more seriously to reduce the number of hits he took.

"Choosing the lesser of two evils..." Obito suddenly had a flash of inspiration and thought of a method. "Kakashi, didn't you say I couldn't win against you? Then do you dare to make a bet with me?" Obito provoked with a smile.

Kakashi's expression remained unchanged. He said indifferently, "Bet on who gets first in the competition? Do you think I'd fall for such a stupid taunt?" Participating in such a meaningless competition was not as good as reading more books.

"Of course not! Don't you think you're so amazing? Then how about we test whose eyesight is stronger, or whose hand speed is faster?" Obito said. "If you win, I won't talk about the competition anymore and I'll treat you to ramen five times. If you lose, you just have to participate in the competition". As long as Kakashi didn't agree, he would keep pestering him about participating in the Young Ninja Tournament, and then Kakashi would naturally agree to this simpler, quicker challenge.

Kakashi didn't rush to agree but asked, "How exactly will we compete?" Obito picked a leaf from a tree next to Kakashi's house, placed it on his palm, and said, "It's very simple. I'll quickly switch the leaf between my left and right hands, and you just have to guess which hand the leaf is in. Isn't it simple?"

Kakashi thought about it and decided that Obito's hand speed couldn't possibly be faster than his eyes, so he readily agreed. He knew Obito's personality; he might pester him all night. It was better to use this simple test to show Obito the gap between them.

Obito put his hand speed to the maximum, wildly shaking his left and right hands, and stopped after about five minutes. "Right hand," Kakashi directly pointed to Obito's right hand, where he had hidden the leaf. "I really don't know where you get the courage to challenge me to this," Kakashi said with some disappointment. He had thought Obito's hand speed would be much faster, but it was just this; the leaf had never left his sight.

Hearing Kakashi's words, Obito instead laughed and asked, "Kakashi, are you sure it's this hand? Once you're sure, you can't change your mind".

"Trying to bluff me? It's the right hand, go ahead and open it," Kakashi didn't change his mind because of Obito's laugh; he just thought Obito was putting on a brave front.

"Then I'll open it," Obito slowly opened his right hand.

I'm attending a funeral today, so I wrote this a bit hastily. If there are any issues, please point them out, and I'll revise them later.