Chapter 1 – The Man Who Walked into the Classroom of Hell

The doors of Tokyo Arcane University loomed before him, polished stone carved with protective runes that shimmered faintly in the morning light. Students bustled in uniforms of varying colors, laughter and chatter echoing across the campus. To them, this was a sanctuary of knowledge and prestige.

But to Tendou Shinsei, it felt like a battlefield.

His hair hung in wild strands down to his shoulders, white as frost yet unkempt, and his face bore a thick, uneven beard. His coat, though newly provided, seemed out of place on his broad frame, his posture weighted by years of war. Compared to the clean-shaven professors and neatly dressed staff, he looked like a relic of a forgotten age—a savage among scholars.

As he stepped into the meeting hall, whispers spread like wildfire.

“Is that him?”
“The war criminal?”
“Why would they let someone like that teach here?”

A line of professors stood waiting. Some glared openly, others avoided his gaze as though his presence stained the air. Only one man met his eyes without wavering: Masamichi Tachibana, the Headmaster.

“Welcome, Tendou Shinsei,” Tachibana said, his voice strong, unflinching. “Regardless of what the world calls you, you stand here as an instructor of this academy. Do you accept this?”

Shinsei bowed his head. His voice was low but steady. “I accept.”

A murmur rippled through the staff. One professor scoffed audibly, another muttered, “A disgrace to our institution.” But Tachibana silenced them with a single look.

That night, Shinsei returned to a quiet wooden house on the edge of the city—his grandmother’s home. A frail woman greeted him with trembling hands and tears in her eyes, as though welcoming a ghost. Beside her stood his younger sister, smiling timidly, her warmth piercing through the darkness in his chest.

It was there, in that home, that Shinsei shaved the beard from his face, cut the tangled strands of hair, and stared into the mirror once again. His reflection was sharper, his crimson eyes clearer, though the scars in his heart remained.

Tomorrow, he would face his true trial.

The door to Class 1-D creaked open, and every pair of eyes inside turned toward him.

This was no ordinary class. These were the children of nobles, of politicians, of powerful bloodlines. Spoiled, arrogant, and untamed. Their desks were littered with snacks, arcane tomes, even magical gadgets. Discipline was a foreign word here.

A smirk spread across one boy’s face. A faint glow sparked at his fingertips, and an eraser, charged with a tiny spell, shot across the room straight at Shinsei’s face.

Without so much as blinking, Shinsei’s hand rose. The eraser stopped inches from his temple, caught between two fingers.

Gasps erupted.

He turned the eraser slowly in his hand, then spoke with a calm voice that cut through the noise.
“My grandmother once told me… everyone sees me as strange. As dangerous. But it is that strangeness which allows me to survive. And survival is all that matters on the battlefield.”

A ripple of unease spread through the room.

At the back, a girl’s voice rang out sharp and cold. Reika Kurogami. Snow-white hair framed her pale face, her crimson-violet eyes gleaming with disdain.
“Why should we accept you? A butcher who slaughtered his own men—teaching us? You’re unfit to stand here.”

Cheers and jeers followed, the room erupting in defiance.
“Send him back!”
“We don’t need a killer!”
“Get out of here!”

Shinsei said nothing. His crimson eyes scanned the room, unwavering. But before the chaos could consume the class, the door opened again.

Headmaster Tachibana entered, his presence enough to silence the uproar.

“You dare insult your instructor before you even face him in battle?” Tachibana’s voice boomed. He gestured to the blackboard, where the students’ grades had been scrawled.
“Look at these scores. Abysmal. You’ve brought shame to this academy. Not one of you has passed a proper combat evaluation.”

The class fell silent, shame creeping across a few faces, though pride kept their chins lifted.

Tachibana’s eyes narrowed. “Tendou Shinsei is not here to coddle you. He is here to make you stronger, whether you despise him or not. And if you doubt him—prove it in combat.”

At once, Reika rose to her feet, her voice cutting the silence. “Then I challenge him. If I win, this man leaves. He has no place here.”

A second voice joined, deep and defiant. Renjiro Arakawa, tall, broad-shouldered, his golden hair shining like fire. He slammed his fist on his desk. “Count me in. If this fossil thinks he can lecture us, let him prove it with his fists.”

The room erupted once more, cries of approval echoing.

Shinsei stood there, motionless, as though the storm of voices meant nothing to him. Finally, he let out a slow breath and spoke.

“If that is what you want… then let us decide it here. If you win, I’ll walk away and never return. But if I win—” His red eyes gleamed, sending a chill through even the boldest of students. “—then I will teach you until the day you graduate. Whether you like it or not.”

The air grew heavy. The students felt it—the presence of a man who had walked through fire, who had stood knee-deep in blood.

For the first time, Class 1-D fell truly silent.

The battle between teacher and students was about to begin.