Whispers drifted through the high-ceilinged classroom of Class 1-A, thick with anticipation. Rumors had been circulating for three days about their temporary homeroom teacher. Word on the school blogs was that they were getting 'Void'—a legendary, dimension-hopping Pro Hero known for his easygoing smile, his world-bending abilities, and a teaching style that was rumored to be incredibly lenient compared to Aizawa’s harsh regimen. "I heard he can travel across parallel realities," Midoriya whispered, his eyes wide as he scribbled furiously in his notebook. "Imagine the kind of combat training we’ll get with someone who has seen entire different worlds!" Scoffing loudly from his desk, Bakugo leaned back, his boots resting heavily on the polished wood. "Like it matters," Bakugo muttered, a small spark popping from his palm. "Whoever they throw at us is just going to be another extra trying to stand in my way." Before Iida could raise his arm to lecture Bakugo about proper desk etiquette, the heavy classroom door slid open. Heavy, uneven footsteps echoed in the sudden silence. Instead of a towering, charismatic figure cloaked in cosmic energy, a thin, gaunt man stepped over the threshold. He wore a cheap, rumpled gray suit that looked two sizes too large for his skeletal frame. His dark hair was shot through with premature streaks of silver, hanging limply over a face that looked as though it hadn't seen a full night's sleep in a decade. Dragging his feet toward the podium, the stranger didn't look at the students. He stopped, gripped the edges of the wooden stand, and let out a wet, rattling cough that shook his entire upper body. Class 1-A watched in stunned, horrified silence as he pulled a gray, threadbare handkerchief from his pocket and pressed it to his mouth. When he pulled it away, dark crimson flecks stained the fabric. Without a word, he folded the cloth, tucked it back into his breast pocket, and gripped the podium once more to steady himself. Silence stretched across the room, heavy and uncomfortable. "Who the hell is this guy?" Bakugo muttered under his breath, his eyes narrowing in immediate disgust. Slowly, the man raised his head. His eyes were entirely hollow, dark pits devoid of the youthful fire that filled the room. They were the eyes of a man who had stared into an abyss, survived it, and regretted the survival every single day. "My name is Arthur Pendelton," he said. His voice was a low, dry rasp, like dry autumn leaves scraping across concrete. "Mr. Aizawa is currently indisposed, and the administration’s original choice—the colorful traveler you call Void—has been reassigned to a border crisis." Midoriya slumped slightly in his seat, his disappointment palpable. "I am your substitute," Arthur continued, his gaze drifting lazily across the rows of eager, youthful faces. "I am not a Pro Hero. I do not possess a license to save people, nor do I have any desire to teach you how to strike a heroic pose for the cameras." Standing up so fast his chair scraped violently against the floor, Bakugo glared at the front of the room. "Are you kidding me?" Bakugo snarled, his palms smoking. "UA is supposed to be the best. Why did they send some dying, quirkless old man to watch over us?" Arthur didn't flinch at the outburst. Instead, his hollow eyes locked onto Bakugo's face, and a cold, chilling stillness settled over his features. To Arthur, the boy didn't look like a prodigy. He looked like a corpse. Arthur’s mind involuntarily flashed back to a muddy trench, to the screaming of teenagers who had also thought they were invincible right before the artillery tore them to pieces. "Katsuki Bakugo," Arthur said softly, his voice devoid of anger, carrying only a flat, clinical detachment. "Quirk: Explosion. You secrete nitroglycerin-like sweat from your palms and ignite it at will." Sparks hissed between Bakugo's fingers, his chest puffing out. "Yeah, that's right," Bakugo sneered. "And it's stronger than anything you've ever seen, old man." "Your quirk is a suicide sentence," Arthur said. Every student in the room froze. Midoriya’s pen stopped mid-stroke. "The human body is not built to withstand constant localized detonations," Arthur explained, his deadpan analysis cutting through the tension like a scalpel. "Every time you detonate those blasts, the shockwaves travel backward through your radius and ulna, micro-fracturing the bone structure of your forearms." Bakugo’s eyes widened slightly, his mouth twisting into a grimace as he tried to hide the sudden tension in his wrists. "By the time you are twenty-five, the cartilage in your wrist joints will be entirely degraded," Arthur continued, stepping out from behind the podium. "Furthermore, your reliance on sweat glands means your combat efficiency drops by eighty percent in sub-zero environments." Leaning forward, Arthur tapped his own temple. "If a villain with a cryo-quirk or a simple fire-suppressant system corners you, you are nothing but a loud, angry boy with brittle bones and useless hands." A suffocating weight descended upon the classroom. Bakugo stood frozen, his mouth half-open, the cocky smirk entirely wiped from his face as his knuckles turned white. Looking past Bakugo, Arthur let his deadpan gaze sweep over the rest of the class. He saw Todoroki’s posture stiffen. He saw Midoriya frantically erasing a line in his notebook. They were so young, so full of idealistic dreams about saving the world with bright smiles and flashy techniques. They had no idea of the sheer, unadulterated brutality of the world waiting for them outside these reinforced walls. To Arthur, they were just lambs marching happily toward a slaughterhouse he had barely managed to crawl out of. Grip tightening on the edge of a stack of papers, Arthur felt a familiar, bitter ache in his chest. He didn't want to be here. He didn't want to look at these children and see the ghosts of his own dead squad staring back at him. "You think this school is a training ground," Arthur said, his voice dropping to a dangerous quiet that forced everyone to lean in. "You think the villains will play by the rules of sports festivals and rescue simulations." Arthur reached into his tattered briefcase, pulling out a thick, heavy manila folder. He calmly tossed the files-folder onto the podium, revealing detailed blueprints of Class 1-A's dorms with red 'X' marks over each student's bed, muttering, "By Friday, half of you would be dead in a real raid."

Chapter 1: Cinders on the Chalkboard