The Royal Military Academy's Impostor Owns a Dungeon [BL]

But who would’ve thought it would actually be possible?!

A while back—

There was the familiar hum. One that both terrified and relieved him.

Sid hadn’t been powered down since he received the ability to move as he pleased. In the time since his repair, he had always been maintained while conscious. Awake. Mobile. As free as he never thought he could be.

Autonomous.

Yet apparently, that freedom was impossible to keep—not if the little master’s next plan was to be done safely.

So Sid had to be turned ”off.” His synapse reactor had to be shut down because it was the only way to reconfigure his spiritual channels without risk.

And it was terrifying.

Sid, a respectable guardian mecha who once stood unshaken before battlefields, did not expect that what would finally make his soul tremble was the prospect of being reduced back into stillness. Reduced to merely existing.

And how could he even explain it? Guardian mechas weren’t supposed to feel fear. They weren’t even supposed to experience what he had already been given. Even if the gift of mobility was taken away, he would still be Sid. Still a guardian mecha.

So even as his spirit shivered, afraid of being confined once again, he did not protest. He allowed himself to be fastened, forcing conviction into his systems, insisting everything would be alright.

But of course, a certain golden-eyed mechanic noticed the truth. Because how could he not, when those hands kept clenching and unclenching?

”Sid, is there anything making you uncomfortable?”

The mecha froze. ”Huh?”

”Is anything stretched oddly? Or unsupported? Would you like to do this lying down?” asked the worried human, craning his head around as though a single bolt out of place might be the cause of Sid’s distress.

What? Sid was struck dumb. And then it clicked.

Oh.

Yes.

The little master was like that. He was definitely like that.

And as though proving the point, the joints Sid had been unconsciously tensing relaxed at once.

This was the same person who asked about the suffering and comfort of a glorified mix of metal and beast parts. The same one who always asked which changes Sid liked or disliked as if his preferences truly mattered.

So if it was this little master... surely, it would be alright.

”I am alright now, little master. You may begin whenever you are ready.”

”That’s great, Sid! And don’t worry, I’ll try not to take too much time!” Luca said with a grin, only to falter. His brows furrowed as if realizing something terrible. ”Wait. That doesn’t sound very reassuring. What I meant is—I’ll be thorough!”

Flustered, he waved his hands, as though desperate not to be misunderstood.

Sid, who had originally been the one struggling with this ordeal, now found himself oddly calm. He even said gently that it was alright if it took longer. But curiosity overcame him, and he asked, ”Why do you not want to take too long, little master?”

Luca scratched the back of his neck shyly. His voice dipped soft. ”Well... I just thought it would be uncomfortable to be stuck, unable to move for a long time. I didn’t much enjoy the feeling, so I figured it would be the same for you. Even D-29 doesn’t like it when I take too long with repairs.”

Ah.

So Sid had been right.

”I see. Thank you for the consideration, little master,” he said, and the words felt heavier than steel within him.

”Oh! It’s nothing. I’ll see you soon, Sid. Just sleep for a bit!” Luca nodded eagerly at him, as if he were sending a child to bed instead of shutting down a sentient guardian mecha.

”I will see you soon, little master,” Sid replied.

And just before the world dimmed, he found himself thinking an absurd thought:

Maybe... maybe he would allow the soles of his feet to be painted any color the little master liked.

And just like that, Sid, the guardian mecha, slumbered.

Only to awaken three space days later.

The first thing he saw was a wobbly yet cheerful human with golden eyes, smiling up at him despite looking like he had wrestled a star and lost.

”Hehehe. Welcome back, Sid.”

”H-hello, little master. I... am back.”

”You can try moving now! I’ve taken out the grips!” Luca shouted happily from below.

Sid obeyed, gingerly shifting his weight forward. His legs moved. His balance held. His systems sang in relief.

The golden-eyed human, however, didn’t even watch the full test. Instead, after confirming the first step, he sagged like wet laundry and shuffled to a random corner. He sat down, slumped against the wall, and with a soft mutter of, ”It’s all good now. I’m so glad...” promptly fell asleep.

”!!!”

Sid rushed over in alarm, convinced the little master had fainted from exhaustion. His hands hovered, afraid to move him, terrified that he had pushed himself too far.

But D-29 cut in sharply. ”The Host is literally just napping this time.”

”...Napping?” Sid echoed, stiff with disbelief.

”Yes! Do not alert the Benefactor. The Host insisted it must be a surprise. Imagine if the Benefactor walked in right now and saw you before the Host could reveal you?!”

Sid froze. He hadn’t thought of that. He wanted to argue, but then D-29’s next words landed like a meteor.

”It took him about eighty hours, nonstop. Repairing and upgrading an existing mecha is far harder than building one from scratch.”

”Eighty... hours?” Sid’s voice rumbled in shock. ”What about breaks? What about rest?”

”The Host didn’t want breaks,” D-29 explained simply. ”He said no one would want their body left open like that. He said it doesn’t feel good.”

Sid stilled. His optics dimmed faintly as he looked at the slumbering boy curled in the corner, utterly defenseless. His processors hummed, and if he had something like a mechanical heart, his chest would have tightened in a way that was not mechanical at all.

His master had really chosen someone far too good.

But his thoughts were cut off by an insistent buzz.

”Now show me!” D-29 chirped excitedly.

Sid blinked. ”Huh? Show you what?”

”The wings, of course!” the little system replied indignantly. ”I want to see if they look better than mine!”

”...What?! Is that why you haven’t been using your mecha form?” Sid demanded. ”You’ve been waiting just to see the final look before revealing yourself?”

”O-of course not!” D-29 sputtered, glitching slightly. ”But according to my research, it is important to be revealed last!”

”Revealed last? But how could you be revealed last when Duke Leander’s mecha will likely be the last one?” Sid asked bluntly.

”!!!”

”H-how could that be?!” wailed the horrified little system, realization dawning that it had made a grave miscalculation.

Sid tilted his head, optics narrowing. ”Also, if you don’t practice flight with your new body, what if you fall? And in front of everyone, no less?”

”!!!”

D-29 buzzed frantically. ”B-but Sid! You also have a new body! What if you fall?!”

”Oh, me?” Sid’s voice rumbled with a hint of smugness. ”If that happens, I’ll hide. Just like this.”

And before the system could argue, Sid—who hadn’t even seen his full reflection yet but could already feel the changes in build, in spiritual channel flow, in raw power—simply vanished from sight.

Gone.

”!!!”

D-29 sputtered in static shock.

Wow. Thought Sid.

The little master really did it.