Kivotos has one strange rule: only Sensei can watch over all the students of the academy city. But what if, on that one crucial day, Sensei had made a different choice?
During a Federal Student Council emergency meeting, Sensei was forced to decide: protect Trinity General School or Gehenna Academy. There was no time. No way to save both. Sensei chose Trinity — and Gehenna was left behind.
That single choice changed everything.
Nagisa Saruyama, the discipline committee chair of Gehenna, was f
What If Sensei Had Chosen Differently - The Reason to Be a Shield—An Unbreakable Adult and a Committee Chair Who Stands Alone
The morning in Gehenna District always begins with the smell of smoke.
This was the third consecutive day. Sensei crouched in front of a pile of rubble, hoisting chunks of concrete in both hands. Heavy. It pulled at the lower back. But that was fine.
"[sarcastic]……There they are again, that person"
The young committee member beside him—apparently named Karen, a short-haired female student—muttered under her breath. Her colleague, wearing the Gehenna Disciplinary Committee armband, shrugged in response.
"[sarcastic]Maybe it's some kind of punishment game"
"[sarcastic]A punishment game where you come every morning?"
"Who knows"
Sensei had heard them. But said nothing. Carried concrete, stacked it, went back for more. That was all. Just repeating that cycle.
Three days ago, insults had been hurled. Two days ago, silent glares. Today was like this. Better than before, probably.
At some distance away, Nagisa was issuing instructions to her subordinates. Long black hair with red streaks. A short sword at her hip. Her uniform collar was fastened neatly and precisely. The voice didn't carry, but watching her subordinates move swiftly made it clear her orders were accurate.
Nagisa didn't look at Sensei. Whether she was processing him as nonexistent or deliberately ignoring him, Sensei couldn't tell. But for just a moment—her hand, flipping through the supply list at the temporary warehouse, stopped. Her eyes flicked toward him.
Just for a moment.
Then her gaze returned, and Nagisa continued giving orders.
Sensei lifted the rubble and thought, (Well, that's how it goes.)
—————
It happened in the early afternoon.
Right after Karen looked up at the sky and murmured "I'm hungry," gunfire erupted from the direction of the outer perimeter.
Dry, rapid bursts. Not one or two shots. Multiple weapons firing simultaneously.
The movements of the Disciplinary Committee members changed. The lazy afternoon air snapped taut in an instant. Nagisa's hand was already on her short sword as she spoke into the radio.
"[serious]Report—the illegal group at the outer perimeter, how many"
The voice that came back was garbled with static. Sensei couldn't make out the details, but Nagisa's face hardened for just a moment.
"[cold]Thirty. Armed. They're targeting the temporary warehouse"
The outer edge of Gehenna District, near the coast—that area was a lawless zone beyond the Federal Student Council's jurisdiction. An illegal occupancy group lurking there was now moving to seize Gehenna's supplies. That much, Sensei understood.
The Disciplinary Committee members gathered. But their numbers were few. Still many were absent due to aftereffects from the previous incident.
Nagisa quickly counted heads, and her brows furrowed slightly. That alone made the severity of the situation clear.
"[serious]I'll take the front. Karen, you handle the east entrance—"
"[serious]The north entrance is understaffed"
Nagisa spread out a map. Her finger traced across it. Calculating. But—there weren't enough people. That much was obvious even to Sensei's eyes.
The north entrance of the temporary warehouse. An old wooden door that still hadn't been reinforced due to damage from the previous incident. There was no personnel to defend it.
Sensei set down the rubble. He walked.
"[serious]Sensei! Where are you going—"
He didn't look back.
—————
He stood in front of the north entrance door.
An old wooden door. Swaying in the wind. There was no committee member to defend it. So if he stood here, that would be enough. That was all there was to it.
Sensei had no weapon. No Halo. That ring of light the students carried—that protective power—Sensei didn't have it. If he got hit here, it would hurt normally.
(Can't be helped.)
The front of the illegal group came into view. Armed. They meant business.
The first one saw Sensei and hesitated for a moment. Maybe he hadn't expected an adult to be here. But that hesitation lasted only a second.
A kick landed in his ribs.
The sensation of his organs shifting. Sensei lurched forward, but he hooked both arms around the door frame and didn't move.
Next, someone grabbed his shoulder and slammed him to the ground.
A crack. From his own head. The taste of dirt mixed with blood. His mouth was cut.
Still, he got up and returned to the door.
"[angry]Why do you keep getting up!"
He didn't know. Sensei himself didn't really know. It wasn't an apology or a sense of justice. Just—the feeling that if he backed down here, it would be over. That was all.
A fist connected with his cheek. His vision warped. But his feet wouldn't move from this spot.
He could tell his face was starting to swell. His cheek and ear were hot. Blood pooled in his mouth.
(It hurts.)
That was all he thought.
—————
Nagisa noticed right after Sensei was slammed to the ground for the third time.
That image caught in the corner of her eye—an adult covered in mud, getting up and returning to the door—made Nagisa pause for just a moment.
Not strength. Not strategy or special power.
Just standing there on sheer stubbornness. Unmoved by anything else.
Nagisa watched it for 0.5 seconds.
"[cold]……Please step aside"
Sensei turned around. His face beginning to swell. Blood at the corner of his mouth.
Nagisa continued. Her voice was quiet. Not an order.
"[cold]If you die, I'll have a hard time sleeping"
Sensei thought for just a second.
"[serious]No"
Nagisa said nothing.
Instead, she pulled out the radio.
"[serious]Everyone, assemble. We're breaking through from the north entrance"
That was all.
The Disciplinary Committee members converged. Nagisa took the lead. There was no hesitation in her movements. The illegal group was overwhelmed. Even with thirty members, their numerical advantage faded before Nagisa's coordinated team.
The battle was brief.
Nagisa's commands were precise, and each committee member's movements connected without waste. Cornered, the illegal group began retreating within ten minutes, fleeing toward the outer edge of Gehenna District.
The gunfire stopped.
Sensei was sitting slumped against the wall near the warehouse entrance. His legs had no strength. The recoil from standing hit all at once.
His face was swollen. The inside of his cheek was cut. His ribs ached. His shoulder ached. He had no energy to do anything.
Karen watched from a distance. Her expression mixed worry with uncertainty about how to approach.
Something dropped onto his knee with a thud.
A first aid kit. A green pouch.
He looked up. Nagisa was standing there, looking down at him. Her expression was unreadable. The same cold face as always. But—something felt different.
"[cold]At least treat yourself"
A brief silence.
"[cold]……You're so clumsy"
She turned away.
Sensei tried to measure the temperature of those words and couldn't quite manage it. Not anger. Not sarcasm either. Exasperation—but it felt like something more than that.
He opened the pouch. Disinfectant and bandages inside. With his swollen hands, Sensei took out the disinfectant and tried to apply it to his cheek.
"[sarcastic]……Let me do it. This is annoying"
Karen came beside him and wordlessly took the pouch. She took out the disinfectant and applied it to Sensei's cheek with rough efficiency.
"Ow"
"[sarcastic]Bear with it"
It was blunt. Her touch conveyed no gentleness. But—she was helping him. That much was certain.
As Karen applied the bandages, her gaze was directed not at Sensei but into empty space.
"[serious]……Why didn't you back down"
Sensei thought for a moment.
"[serious]Because I thought if I backed down, it would be over"
Karen said nothing. The finger pressing the bandage became slightly more careful.
—————
While issuing cleanup orders, Nagisa's back came into view.
Her uniform collar was slightly askew. From her neck across her left shoulder, faintly visible—old, broad scars. Burn marks.
Not just one. The area was extensive. From some explosion, or perhaps—Sensei didn't know the details. But he understood those were scars from conflict. From a long struggle where no one came to help, yet she still stood alone. Those were the marks of that time.
Sensei's hands stopped.
He said nothing. Asked nothing.
Nagisa had already straightened her collar. Whether she hadn't noticed or had noticed and was ignoring it, he couldn't tell. Either way, that was fine.
But—something that had been trying to end itself through apology shifted quietly into a different shape inside Sensei. Not an apology. Not forgiveness either. To stand here together. That was the reason Sensei remained, he felt.
If he put it into words, it would become a lie, so Sensei said nothing. He just murmured "thank you" to Karen as she finished applying the bandages, and stood up with his swollen face.
—————
He arrived back at Schale as the streetlights of Gehenna District began to flicker on.
The stairs of the Federal Commons felt steeper than usual. His ribs ached, and he gasped with each step. He opened the third-floor door and turned on the lights. The fluorescent tube illuminated with its usual dull brightness.
There was a piece of paper on the desk.
Sensei approached and picked it up. An envelope from the Federal Assembly. A formal, certified-mail style format.
He read it.
Read it again.
The currently issued emergency declaration is scheduled to be lifted in five days. After that, Schale's access rights to Gehenna District will expire.
——Five days.
Sensei collapsed onto the sofa. His swollen face pressed against the pillow and hurt, but he had no energy to get up. He stared at the ceiling. The fluorescent light cast its quiet white glow.
Today, Nagisa had spoken to him for the first time in the form of a request. Karen had applied bandages for him. Certainly—they had gotten slightly closer than yesterday.
But five days.
That was all there was.
A sheet from the stack of Gehenna damage reports on the desk's edge fell in the air conditioning breeze. A small rustle. Sensei reached out and picked it up, then began reading again.
A string of numbers. But in each one, someone's time was embedded.
What could be done in five days—the answer wasn't yet clear. But his hands didn't stop moving.