Title: Vitriolic Best Buds
Author: Kristen Sharpe
Date: January 3, 2015 Edited: February 6, 2015
Rating: K
Warnings: None.
Continuity: Any
Disclaimer: "Ao no Exorcist/Blue Exorcist" belongs to Kazue Katou, Shueisha, Aniplex, and various other parties.

Author's Note: This was written for the fandom_stocking exchange on Dreamwidth, specifically to fill bridgetmkennitt's request for more fics in this fandom. Co-authored by SageSK as most of the dialogue comes from a chat season between us.

Rin and Suguro were at each other's throats again. About what Yukio wasn't sure. Rin had spent the weekend muttering and growling under his breath, but deciphering his brother's nonsensical ranting was nigh-impossible. Most likely, the argument had something to do with the students' last mission. Rin had been reckless again, and Suguro seemed to take Rin's failure at teamwork as a personal insult.

Yukio understood the frustration. He only wished Suguro could find a more mature way of venting it. Sadly, Suguro, for all his talent, was surprisingly like Rin in temperament. Which made their clashes as inevitable as they were harmless.

On the bright side, their volatile tempers insured that the latest feud would blow up and over soon enough.

Unfortunately, Yukio hadn't anticipated just how and where the blow up would occur. And, it took an effort of will for him to keep his face impassive when he entered the cram school classroom to find his brother pinned under Suguro's arm, bellowing at the top of his lungs.

Composing himself, Yukio raised his voice to ask, "Exactly what is this?"

"An exorcism!" Suguro shouted.

"Oi!" Rin barked, hands prying at Suguro's arm.

Yukio considered the situation, adjusting his glasses. "...I don't believe that is a proper hold for a demon of that level."

Rin released a strangled, "Yukio, you traitor!" as Suguro answered, "I have my methods! Tying his tail in a knot sounds promising."

"Not during classtime." That ultimatum delivered, Yukio continued to the lectern to take out his class notes.

"Then, I request permission to leave!" said Suguro.

Yukio frowned. Suguro wasn't someone who skipped class. And, it wouldn't be good to let him start such habits. He opened his mouth to order the both of them to their seats. Then, he imagined the glares and growls that would be disrupting his class for the next hour and sighed. "Please resolve the matter in the hall. Without damaging the facilities."

"Thank you, Sir." And, with that, Suguro dragged a flailing Rin for the door.

"I'll remember this at Christmas!" Rin shouted as the door slammed shut behind him.

Yukio glanced over the rest of the class and found nearly identical looks of surprise on the faces of everyone but Takara, who was ignoring them all as usual.

"Er... Teach..." Shima began.

There was a loud thud from the hall.

Looking nervously at the door, Miwa finished the thought for him. "If Okumura really decides to fight..."

Metal - metal that had better not be part of the plumbing - clanged.

Yukio shuffled his notes into order. "Mr. Okumura is quite skilled in controlling himself during... physical altercations." He ignored another series of thumps from the hall. It was true, after all. Rin had engaged in brawls for years, and he always controlled his unnatural strength enough that his opponents walked away with nothing worse than swelling and broken cartilage.

Feigning boredom, Kamiki sniffed, "In other words, he's not going to hurt Bon-Bon... much."

Seated in front of the other girl, Shiemi cast her own worried look toward the door. "Will Rin get in trouble?"

Honestly, Rin should be in trouble for being reckless in the first place and causing this disruption, but Suguro had been the one to start the violence.

"I'm prepared to ignore this so long as the matter is resolved," Yukio answered. Then, he schooled his features into a no-nonsense frown. "Now, class will begin."

For the next fifteen minutes, Yukio lectured the class on the varied uses of holly, raising his voice as needed to cover the sounds of yelling, crashing, and at least two very disturbing cracks. Then, the hallway fell silent. Caught almost shouting in the sudden silence, Yukio faltered.

Someone tittered.

Yukio glared out at the class.

Then, laughter started in earnest. From the hallway.

Yukio huffed out an irritable breath and turned to draw a quick diagram on the board while he waited. It should be any time now.

True to his prediction, the door swung open minutes later. Suguro and his brother stood framed in the doorway, looking sober. To say they were "disheveled" was an understatement. They were filthy, wreathed in toilet paper, and had matching black eyes. Additionally, Rin seemed to have lost a sleeve, and Suguro's tie was torn and hanging in shreds.

Yukio eyed them a minute. "Feeling better?"

Suguro exchanged a look with Rin. "Kinda."

"Sorta," said Rin.

Yukio sighed. "Please take your seats."

The remainder of the class was peaceful, though Yukio wasn't sure how much the students actually absorbed. Finishing his lecture, he dismissed the students and then eyed the two troublemakers.

Suguro had approached Rin's desk, squinting at the smaller teen through his good eye. The other was purpling and had swollen further. He was apparently quick to notice that, in contrast, Rin's eye was already fully healed thanks to his demon heritage.

"Cheater," he grunted.

"Jealous," Rin returned.

The two then headed for the door, bickering good-naturedly.

Yukio heaved a fresh sigh and smiled wryly. Maybe his brother finally finding the friendship and acceptance he'd always craved was worth a little disruption.

But, he was still giving them all a pop quiz on holly tomorrow.

Author's Note: Yes, the title comes from the trope of the same name.