A/N: sLAMS DOWN THE DOOR BECAUSE KARMAGISA WEEK HAS ARRIVED.

ARE YOU READY FOR THESE GAY NERDS, BECAUSE I AM (for once)

Prompt: Past

There was a strange redhead in Nagisa's class. He seemed smart despite the way he often slacked off in work, which admittedly made Nagisa a little jealous if he was honest. Despite how hard Nagisa tried, it seemed like no matter what his grades still wouldn't be near the top or even in the middle. His English wasn't half-bad though, but his grades were nothing compared to the other kids in class.

Nagisa was doomed to fall down to join Class E, and he knew it.

He could still enjoy how nice life was until then though. Nagisa still had some time before he was doomed to rank low in the hierarchy of the school, and he was determined to do as well as he could until then. So until that day would come, Nagisa would watch and try to pay attention until his eyes would inevitably drift back to land on the shocking red hair. Sometimes when Nagisa would give up on trying to understand what the teacher was trying to force into their heads, he would make up stories for the redhead. The stories differed on many different things, but somehow the redhead always managed to save the day and save the heroine no matter what.

A few weeks later and Nagisa finally learned the name of the red headed boy from passing students who were complaining of how he always seemed to be at the top no matter what. It had took Nagisa a minute to connect the dots and figure out just who 'Karma Akabane' was, but it gave Nagisa a strange, light feeling when he did. It was always nice to know what your prince's name was after all.

Things were quiet for a while, and nothing new happened. Nagisa stopped making up stories in his head with Karma as the lead. As much fun as it was to make the already attention-catching boy more interesting, exams were coming up soon. Nagisa wanted to at least have a fighting chance, so he was stuck trying to force himself to understand all the information the teacher was giving him. It wasn't until a few more weeks later that Nagisa even remembered Karma was in his class let alone the fact Nagisa had used the redhead as a protagonist in his daydreams although Karma still managed to catch his attention again whenever the redhead walked out of class for one reason or another.

"He's gonna be the director for Sonic Ninja?! Awesome!"

The sudden voice from behind Nagisa made him freeze before he turned to see a familiar person staring over his shoulder, looking at the magazine in Nagisa's hands with great interest. It took Nagisa a moment to register what the other said and react as Karma looked at him with excitement clear in his eyes. Karma continued on as though he talked to Nagisa thousands of times. As if they were friends.

"We should totally go watch it later, Nagisa!"

A smile, albeit somewhat uncertain, grew on Nagisa's lips. This was his chance to see more of Karma and learn more about him than what rumours told him.

"Yeah."

Outside the window, a butterfly began to beat its wings softly before taking off into the sky.

Nagisa was both surprised and unsurprised when he found out that Karma had been dropped into Class E as well. He had heard about the incident with Karma's teacher, but a small part of him still wondered if Karma's grades were good enough to keep him out of Class E. It seemed like even with the grades the school always demanded its students to have still wasn't enough to save Karma from the dreadful fate of Class E. And yet, Nagisa wondered if Class E wasn't a better fit for someone like Karma…

Thoughts of Karma were soon forgotten as Nagisa's mind was overrun by the questions that came with meeting Korosensei and learning about the mission Class E was given. Although, there was still a small part of Nagisa that wondered how Karma would react when he finally came back to school. Nagisa had no questions about whether or not Karma would try to kill Korosensei though.. A challenge like this would definitely catch Karma's attention, especially after his last teacher.

That being said, Nagisa's shock when first seeing Karma again was mostly due to the fact there was a suddenly a person standing on top of the hill watching them. Nagisa blinked before a small smile found its way on his mouth.

"Karma… You've returned."

The wind picked up behind Karma, making his hair fly as his smirk grew.

"Yo, Nagisa. Been a while."

Karma walked towards the group. His eyes lingered on Nagisa before landing on Korosensei for the first time. His smile seemed to grow in anticipation as he began talking casually to Korosensei. The sudden movement of a butterfly taking off caught Nagisa's attention for a brief second before he refocused on the scene taking place between Karma and Korosensei. Nagisa watched Karma warily as the anticipation built. Others might not know how Karma acted, but the time Nagisa had spent with Karma had taught him the other was up to something. There was no way that Karma would be so openly casual unless-

Korosensei's tentacle began to fall apart in Karma's hand as Karma revealed a knife hidden up his sleeve. Karma stabbed harshly, aiming to kill, only to hit air. Gasps filled the air when the class figured out what had happened. Korosensei stared at Karma several feet away, looking at Karma with a sense of realization and a tinge of horror. Karma's smirk grew, and everyone knew that Class E was about to change once more.

And yet, Nagisa couldn't say he disliked the change that was soon to come.

Nagisa's heart was pounding loudly in his chest. He didn't know whether or not his anxiety was showing on his face. Nagisa really hoped it wasn't. The last thing he needed was Karma knowing that his words and tactics were getting to Nagisa and affecting him more than he would like.

Nagisa forced his hands to stop shaking as he stepped out of the bush. He already missed the safety the dropped gun had given him as well as the advantage of being hidden, but there was no way he could get away with staying as he was. If Nagisa had remained hidden and shot Karma from the bush, there would be no good resolution. The other team would never respect him or his decision if Nagisa hid like a coward the whole time.

Nagisa spotted Karma walking towards him. Their eyes met, and there was a sharp, dangerous intensity shared between them. This was it. They were the only two left in the game of survival. Korosensei's fate was resting in the palms of their hands, and everyone knew it. The air seemed to crackle as they stared each other down, searching for weaknesses and waiting for the right moment to stri-

Karma flinched forward, and then suddenly they were running towards each other with knives raised. The knives were rubber and incapable of killing anyone, but Nagisa almost forgot that in the wake of viciously thrusting his knife out and aiming for any weak spot available. Karma blocked with his arm, forcing both boys at a standstill.

"I'll help him!"

"I'll kill him!"

The words poured out of Nagisa's and Karma's mouths, roaring with a need to win for their respective causes. An abrupt kick to the chest sent Nagisa flying backwards. He jumped up quickly and assessed Karma's stance and balance. Nagisa darted forward again, and the next few minutes were lost in a flurry of action. Kicks were landed, and blows exchanged. Nagisa couldn't even pinpoint where half of his pains were anymore, only realizing they were there before moving to land another attack on Karma. There was a flutter of panic in Nagisa's heart after he punched Karma straight in the face only to have Karma smile blankly at him while plainly stating the words "Is that it?"

Nagisa could barely keep up with all of the movements that were happening but at the same time his eyes managed to see everything, and his body somehow knew how to react. Everything seemed to slow down when Karma had finally managed to make Nagisa stay down. Nagisa stayed still, waiting as Karma walked away to retrieve one of the knives that had fallen earlier. The moment Karma stabbed downwards, Nagisa returned his attack with a sharp stab upwards, succeeding in not only blocking Karma's attack but surprising the other enough that he bit his tongue as well.

When Nagisa looked back on the day, he would revel in the look of shock on Karma's face when Nagisa's knife flew by, and Nagisa himself was launched at Karma. They tumbled to the ground as Nagisa tried with all of his might to make the other stay down.

"I...will...make you listen!"

His arms clung tightly to Karma's neck. Nagisa was cutting off Karma's air circulation, and he knew it. He could feel the bulging pockets in Karma's clothes dig into his skin as Karma squirmed around beneath him in an attempt to escape Nagisa's grasp. His ears perked up at the whistle of the plastic knife cutting through the air and stopping above his head. Nagisa gritted his teeth and prepared for the pain in the back of his head. And then…

"That's it. I surrender."

Nagisa felt the other relax underneath him, but he still clung tight in case it was a ploy. It wasn't until Karasuma announced the end of the battle that Nagisa loosened his grip. He pulled himself back some only to fall forward next to Karma. There was still an underlying sense of disbelief even as Karma explained why he had given up. Joking words were shared between the two, and then suddenly there was a hand in front of Nagisa's face. A small smile appeared on Nagisa's face as he took it and stood up next to Karma.

As Nagisa stood and looked over the area that was so recently a battlefield for Class E and the ultimate determinate for the fate of their teacher, Nagisa wondered if the butterflies were always this beautiful or if it was simply because of the moment's sanctity itself that enhanced their loveliness.

They were leaning against a tree doing nothing but watching the fields around them. There were no words exchanged as the air between the two seemed to allow only thoughts. In that moment, silence reigned.

Until Karma opened his mouth.

"Hey, Nagisa. Have you ever heard of something called the butterfly effect?"

Nagisa's eyebrows furrowed as he shuffled some so that he could view Karma's face better. Karma's seriousness over the sudden subject was strange if Nagisa was honest. He hadn't heard much about the butterfly effect though, so maybe the topic at hand was more important than Nagisa had originally thought? Nagisa ran over what little he knew of the butterfly effect and came up blank aside from the part where he figured it had something to do with butterflies and hurricanes.

"A little bit but not enough to really know what it is."

Karma hummed lowly, a smirk returning to his face.

"Its this saying that goes "If you step on a butterfly today, a hurricane will happen on the other side of the world. But the saying means more than hurricanes and butterflies.. It's means that all the little choices we have done and made effect where we are today and what all has happened around us."

Nagisa blinked. Well...That didn't do much to dull his confusion. Nagisa's thoughts trailed off as he tried to understand why Karma was thinking about choices.

"We've had it happen to us too, you know. Like when we first met. Who's to say that if you hadn't been reading that exact magazine that I would have ever asked you to see the movie?"

Nagisa made a small noise of realization as he thought over what Karma said. When Karma put it like that, it made sense. Nagisa hummed as he began to ponder some of their other moments that were big effects in their lives. He snapped his fingers when he finally found an event that fit the bill.

"Like when you first came back to school? Despite not seeing me for a long time after we first met, you still were quick to talk to me and hang around me. I was even the first person you talked to when you first came back if I'm not mistaken."

Karma nodded and continued on with another piece of their past that helped to push them where they were today.

"Yeah. There's also the time where we fought over whether or not to kill Korosensei. If I had kept fighting and not given in…"

Nagisa picked up where he left off as a feeling of deeper realization dawned on him.

"Who knows whether or not we could have really patched that up…"

Nagisa's words trailed off as he thought deeper. It was so strange to think that all the little things and big things that were said and done could have such an enormous effect on their future. Nagisa was struck with the sudden fear that even a small twitch could end the peace and happiness he and Karma shared now. If little things caused good things to happen, it only made sense that it could make bad things happen as well. Nagisa bit his lip as anxiety began to build in his chest like thousands of bees buzzing. Fingers intertangled with Nagisa's own fingers, causing Nagisa to look at Karma. Karma chuckled and rolled his eyes.

"Don't worry about it, Nagisa. Even little butterflies couldn't tear me away from your side anymore. No matter what happens or where we go, we'll always be there with each other. Promise?"

Nagisa stared at Karma with shock clear in his eyes before it turned into something else, something more soft and warm. Nagisa laughed as the happy smile returned to his face.

"Promise."