The Joker (Kuroko no Basket insert)

The cafeteria erupted with its usual lunchtime pandemonium - a symphony of clattering trays and animated chatter that filled every corner of the space. Taro approached their regular table, his mind already drifting to the upcoming game against Hakuba High later that afternoon. He'd barely managed to plant his but on the chair before a familiar hurricane of energy intercepted his path.

"MY RIVAL!" Hoshiumi proclaimed, launching himself onto his chair with one foot dramatically planted on the table. His body vibrated with such intensity that nearby students instinctively leaned away. "I've been waiting for you! Our current score stands at 22-21 in your favor, but today that changes!"

He whipped out a small notebook from his pocket. The cover was adorned with what appeared to be hand-drawn flames and the words "RIVALRY" in bold letters. Various tabs stuck out from the pages, each one carefully labeled with different competition categories.

Whoosh! Hirugami's hand materialized, gently but firmly pulling Hoshiumi back down. "Manners exist, you know, we sit around the table" he deadpanned, his voice the perfect counterpoint to Hoshiumi's wild energy.

Erina's eye twitched. Her chopsticks, held in her hand, were pointed directly at Hoshiumi like a weapon. "If you ever put your foot on my table again," she whispered, her voice colder than ice, "you'll be eating through a tube for the entirety of high school."

"EEEEP!" Hoshiumi yelped, his survival instincts kicking in fast. The transformation was instantaneous: from passionate rival to terrified child. But even that couldn't suppress his competitive spirit for long.

Artoria, elegant as always, sipped her tea with the composure of a queen. A hint of amusement played on her lips as she watched the scene unfold. "Perhaps we could all enjoy our lunch first?" she suggested, her voice carrying a gentle authority that seemed to momentarily calm even Hoshiumi's boundless energy.

Taro settled into his seat, carefully unwrapping his bento. The familiar aroma of his mother's cooking wafted through the air - perfectly grilled salmon, tamago, and seasonal vegetables arranged with care. He noticed Hoshiumi fidgeting in his seat, clearly struggling to contain his competitive spirit long enough to eat his own lunch.

"The food will get cold," Hirugami reminded them, already halfway through his own meal. His practical nature always seemed to ground their more eccentric moments.

Kazuto, absorbed in his handheld game console, mumbled between bites, "Better eat while you can. You know how he gets when he's excited about a new competition."

Hoshiumi completely ignoring his food, flipped open his notebook anyway, the pages filled with meticulous records in his energetic scrawl:

Basketball 1v1: Taro's Victory (Expected from my rival!) 

Arm Wrestling: Taro's Victory (But next time!) 

100m Sprint: My Victory! (Speedster!) 

Hopscotch: Taro's Victory (A fluke!) 

Rock Paper Scissors: FORBIDDEN (Too many ties - 30 matches without resolution) 

Vertical Jump Contest: MY VICTORY! (The power of determination!)

"Look!" Hoshiumi thrust the notebook forward, his finger jabbing at the latest entry while simultaneously attempting to shovel rice into his mouth. "I've discovered a new category for us to compete in after lunch! CHESS!"

Taro paused thoughtfully, savoring a bite of his mother's tamago. "Chess?" he repeated, raising an eyebrow. "That's... surprisingly structured for you, Hoshiumi-kun."

"OF COURSE!" Hoshiumi declared, rice grain sticking to his cheek. "A true rival must master ALL forms of competition! Besides, I've been studying! Did you know the horse moves in an L-shape? GENIUS!"

Erina sighed, delicately wiping her mouth with a napkin. "At least it's quieter than your usual challenges. The library should appreciate that."

"About that..." Hoshiumi's eyes sparkled with dangerous intensity. "I was thinking we could modify the rules! Maybe add some exercise between moves, or—"

"No," came the collective response from the entire table.

The group fell into a comfortable rhythm of eating and chatting. Artoria shared details about her upcoming tournament, while Kazuto described his latest gaming achievements. Even Hoshiumi managed to focus on his lunch, though his leg bounced continuously under the table with barely contained excitement.

Taro listened to his friends' conversations, occasionally nodding or offering brief comments. His thoughts drifted between the upcoming basketball game against Hakuba High and Hoshiumi's latest challenge. There was something endearing about his self-proclaimed rival's endless enthusiasm, even if it sometimes bordered on exhausting.

"The library has a chess setup," Hirugami mentioned as they finished their meals. "Though I should probably come along to ensure you don't get banned. Again."

"That was ONE TIME!" Hoshiumi protested, practically vibrating in his seat now that lunch was nearly over. "And how was I supposed to know you couldn't practice your jumps in there?"

Taro carefully packed away his empty bento box. "One quick game," he agreed, unable to suppress a small smile at Hoshiumi's immediate explosion of joy.

"YOSH!" Hoshiumi leaped to his feet, gathering his things with lightning speed. "TO THE BATTLEFIELD OF KINGS AND QUEENS! Come, Hirugami! You shall witness history!"

Before anyone could blink, Hoshiumi had grabbed Hirugami's arm and was already dragging him toward the library, their friend's resigned expression suggesting this was far from the first time he'd been volunteered as a referee.

"Good luck with your game later," Artoria called after Taro as he stood to follow at a more reasonable pace.

"Try not to let him turn chess into an extreme sport" Erina added, though there was fondness beneath her exasperation.

Taro nodded, gathering his things. As he walked toward the library, he could hear Hoshiumi's voice echoing down the hallway, apparently explaining his "secret chess strategy" to a long-suffering Hirugami. Something about the power of the square and determination being more important than actually knowing how the pieces moved.

The library came into view, and through the window, Taro could see Hoshiumi already seated at the chess table, arranging and rearranging the pieces with intense concentration. Hirugami stood nearby, looking like he was seriously reconsidering some of his life choices that had led to this moment.

"AHA!" Hoshiumi's voice carried through the library doors as Taro entered. "My rival arrives! I've already set up the board according to the diagram I memorized! Though I might have mixed up the bishops and the pointy-hat ones..."

"Those are the same piece," Hirugami muttered, pinching the bridge of his nose.

Taro took his seat across from Hoshiumi, noting with amusement that several pieces were indeed in the wrong positions. "Shall we begin?"

"The rules are simple enough!" Hoshiumi declared in what he thought was a whisper but was actually more of a stage whisper. "These little ones move forward, the horse jumps in an L, and the pointy-headed ones go diagonal! PERFECT FOR A NEW CHALLENGE!"

Taro simply nodded, his expression unreadable as he helped correct the board setup and made his first move with casual precision.

Three moves later, Hoshiumi's confidence began to crack as he watched Taro systematically dismantle his defenses. His eyes darted between the pieces, sweat forming on his brow.

"Wait..." he muttered, realization dawning. "You... you actually know how to play this, don't you?"

Taro's small smile was all the answer he needed.

"THEN I PROPOSE A MODIFICATION!" Hoshiumi whispered frantically. "Chess boxing! We alternate between chess and boxing rounds! That way my ENERGY can—"

Countless glares from nearby students answered him. If looks could kill, Hoshiumi would have disintegrated on the spot. He shrank in his seat, momentarily cowed by the collective force of the library's disapproval.

The game continued, as Taro realized that Hoshiumi's strategy was pure chaos. His moves were less "chess" and more "moving pieces in directions they're legally allowed to go."

Eight moves. Silence.

"Checkmate," Taro whispered.

Hoshiumi stared at the board, his mouth hanging open. "WHAT?!" he suddenly bellowed, completely forgetting they were in a library. "BUT I STUDIED THE SICILIAN DEFENSE BEFORE THIS! I EVEN WATCHED THE QUEEN'S GAMBIT!"

The librarian's head snapped up, her glasses glinting with barely contained fury.

"THIS IS WHY YOU'RE MY RIVAL!" Hoshiumi continued, jumping to his feet. "ALWAYS SEEING THROUGH MY TECHNIQUES!"

"Young man," the librarian began, her voice a sharp whisper, "you need to—"

"I WILL RUN LAPS AROUND THE SCHOOL TO STRENGTHEN MY CHESS MIND!" Hoshiumi's voice crescendoed.

In one swift motion, the librarian took Hoshiumi by the arm, swiftly escorting the protesting rival toward the exit.

"BUT, BUT—" Hoshiumi's final protest was cut short as the library door closed behind him.

Taro simply began resetting the chess pieces as he started playing against Hirugami, a faint smile playing at the corners of his mouth. Through the window, he could see Hoshiumi already starting his self-imposed punishment/training, notebook in hand, presumably adding another tally to their ongoing rivalry record.

"He is... unique," Hirugami said resignedly.

"Maa... he keeps things interesting," Taro replied, his thoughts already turning to the afternoon's game. He could hear Hoshiumi outside, declaring how he would master chess through determination.

As they left the library, "I should probably make sure he actually goes to clas" Hirugami sighed, watching Hoshiumi's continuous laps. "Someone has to be the voice of reason."

"TARO!" Hoshiumi's voice carried across the courtyard. He was on what appeared to be his fifteenth lap. "AFTER YOU DEFEAT HAKUBA, WE'LL HAVE AN EPIC BATTLE OF THUMB WAR! I'VE ALREADY ADDED IT TO PAGE 47 OF THE RIVALRY NOTEBOOK!"

"Shouldn't you be going to your classroom?" Hirugami called back.

"A TRUE RIVAL NEVER RESTS!" Hoshiumi shouted, starting another lap. "BESIDES, I'M MULTITASKING! EACH LAP IMPROVES MY CHESS SKILLS BY 0.5%!"

Taro shook his head with a small smile as he headed back to class for the remaining afternoon lessons. The game against Hakuba would come after school, but somehow, Hoshiumi's boundless energy had already helped clear his mind. Sometimes, he realized, having a self-proclaimed "eternal rival" wasn't such a bad thing.

"Good luck in your game" Hirugami voice echoed as Taro reached his classroom door. 

Inside, as Taro sat down at his desk, he couldn't help but smile. The notebook, the challenges, the endless energy, it was all ridiculous. But somehow, it had become part of his daily life, adding color to his world in unexpected ways. Now, though, it was nearing game time. Hakuba High was waiting and he planned to crush them.

After all, he couldn't let his "rival" down.