It was at the end of Obito's 5th grade year that Kakashi left.

Obito was just 11 yrs old and his entire world was crushed. Here he was, staying behind without his best friend and he was going to a new school to start junior high next year. His best friend in the world was leaving. What was he going to do without him?

Over the past year, Kakashi was hanging out with him less and less. His father was sick and he couldn't play with Obito and Rin as much as before. That was ok though, Obito understood he needed to be there for his father. That didn't change the fact that he really missed hanging out with his friend.

Then at the end of the year, Kakashi finally left.

When Kakashi first went away, Obito made the effort to keep in touch and it worked for a little while. Obito called him everyday, just to chat about nothing. Small talk. Maybe even to check in and see how he was doing. But as time went on, it got harder to get a hold of Kakashi. He always seemed distracted or busy. His father was sick after all.

Over time, Obito started calling less and less. Not that he didn't want to call, it just seemed Kakashi was always busy or another family member answered and told him to call later. He figured Kakashi had a lot on his plate and he would reach out when he was ready.

Except, he never called back.

Obito was utterly devastated. He thought he had lost his best friend forever.

Then, by the end of Obito's freshman year, Kakashi came back. It had been 4 years. And Kakashi and his father moved back into their old empty house across the street. Things were going to go back to the way they were. He had his best friend back!

Except, it was different. Kakashi now wore a mask covering half his features. Which was weird-- He never used to wear a mask like that. But Obito didn't want to judge. He and Kakashi used to pretend to be ninjas when they were kids. Maybe it's a fashion statement. But, there was something else different. It wasn't obvious at first, but something major was changed in Kakashi.

Obito and Rin came to talk to him the day he came back. Obito was so excited to see him. He couldn't wait to tell Kakashi how much he's grown, that he was changed. He was no longer the chubby, failing student that constantly needed his help. Now, he was a great student and fully functional on his own. He no longer needed anyone's help at school anymore.

Obito told him about his dream to become SCP. How hard he's worked the past 4 years. Obito felt proud. He's accomplished so much while Kakashi was gone.

But Kakashi didn't seem as happy to see them as Obito thought he would be. Things had gotten awkward between them. Kakashi was very distant and cold.

Then, Kakashi joined Obito's high school for sophomore year. Obito was so happy; he would see Kakashi at his school. Maybe Kakashi just needed a bit more time to adjust to moving back into town.

And then Kakashi ran for Sophomore Class President... against him. That was alright, thought Obito. He welcomed the challenge. Kakashi was free to run for that position if he wanted to. Obito wouldn't stop him. And, there was no way Kakashi would win. He was only at school for 2 months.

But of course, Kakashi did win. Obito was shocked at first, but it was ok. He was still on student council as the Sophomore Class COPR. They would work together on the board to improve the school.

But Obito was so wrong. They had different ideas on how to run the sophomore class. 

Throughout the year, Kakashi shot down every single one of his ideas. And they were great ideas... Start mentor program with juniors? Career Day preview? Spring Formal at a fancy hotel instead of the gym? Halloween haunted house instead of just making cookies? Club competitions, etc. Kakashi shot them all fucking down. 

Obito just didn't understand it; He felt so discouraged by the whole thing. Kakashi simply told him they went against high school tradition and cost too much of the budget. So Obito said he'll do fundraisers. Then Kakashi shot back saying fundraisers also cost money.

As each meeting passed, Obito lost more of his patience. Why was Kakashi treating him like this? Was he upset about Obito running against him for class president? Obito just couldn't figure it out.

What made things more weird, everytime Obito looked at Kakashi, it seemed like he was always watching him, glaring daggers at him for some reason. This animosity was uncalled for and it made no sense.

It really started to piss him off.

So, Obito started outspokenly fighting against Kakashi and with a fiery intensity. He argued what was the point of them being on the class board if they weren't innovating or creating anything new? Kakashi calmly said they were there to maintain customs, not to change them or create new ones. They had to follow the rules. It was like a constant battle between them.

And then, there was the incident that broke the camel's back.

It was for the Sophomore Year End Event. At one of the year's last student council meetings, Obito went against Kakashi's wishes and shouted out during the meeting that the Sophomore Class Board will hold one last big fundraiser for the school.

The SCP at the time, loved the idea. They told Kakashi they would love to see the event happen. So Kakashi felt pressured to do it.

After the meeting, Kakashi reprimanded Obito for challenging his authority. He threatened to end his dream for good.

Of course, Obito didn't listen. At that point, he stopped listening to Kakashi. He went on and organized the whole thing. And since Kakashi held him back the entire year, he had a lot of ideas. He knew exactly how to plan the event and have everything go smoothly.

And it was a fucking success! He raised back all the money he used for the event and then some. All the students had fun and the year ended with a bang. It was freaking amazing!

In retaliation, Kakashi made sure Obito wasn't in student council the following year.

.....

Present

On his way home from work, Obito thought about the incident. It was just last year when all this animosity between them started. Perhaps they just grew apart? It just seemed like they couldn't agree on anything while they were on the sophomore class board. It was a constant struggle just trying to work together.

It's weird how close they used to be. Something must've happened to Kakashi when he was gone for 4 years. There's no other way to explain it.

When Kakashi came back, they should've been able to rekindle their friendship, right? They were close childhood friends and they were neighbors.

Perhaps, they both changed a lot since they were kids. But Obito felt like he was still the same person as he was when he was a kid. He's just more focused and motivated now.

Obito remembers the way Kakashi looked at him at the grocery store. He smiled at him-- Like actually smiled, not a smug smirk or half smile. It was almost as if they were friends again. Maybe now, things can start improving in their relationship.

Despite the crazy war between them, Obito did want his friend back. It's just that, becoming SCP has always been his goal, and Kakashi is still in his way to get there.

____

A/N: Woohooo! Crazy backstory chapter. Well, not crazy... just regular, I guess. :|

So this is the reason why Obito and Kakashi hate eachother... even though they were really close as kids. I hope this is convincing enough. I dunno, what do you guys think? :o

The next chapter is a bit short. I might just release it tomorrow as well. I don't know, we'll see.

Btw, I'm working on a oneshot that stars these two lovely idiots. It's ending up longer than I'd like, but hopefully it will come out soon. :3