The Royal Military Academy's Impostor Owns a Dungeon [BL] Chapter 621: The Phantom Guardian

A ghost.

A phantom.

Or at least, that was what Sid thought it would be like. Because surely, a guardian cha like him could not possibly know what it truly ant to be one.

And yet, for a fleeting instant, right as he disappeared, the newly upgraded Sid believed he was as close to a phantom as one could possibly be without actually dying.

It was downright impressive.

For the first ti, he fully understood why the little master had kept asking him about his original build.

Back then, Luca had been confused why Sid—who was supposed to excel at light cha combat—was heavier than most light models. The boy’s golden eyes had squinted with suspicion, hands on his hips, muttering about possible design oddities and balance.

For a mont, Luca had tried to understand if he had missed a particular reason why the cha was designed like that.

But apparently, Sid hadn’t been designed with a specific combat style in mind at all.

Luca had eventually figured it out: Sid’s blueprint was closer to those one-form builds, where the entire fra existed as a single fixed design.

Of course, Sid had assud it was simply because he was... well, an heirloom.

"An Imperial Heirloom?" the little master had asked during their upgrade discussion, his voice full of disbelief.

"Yes, little master," Sid had replied calmly. "I am ant to be passed from generation to generation. To whoever can form the necessary bond, and when the current master deems it fit."

"WHAT?!" Luca had nearly fallen backward. "So you’ve had... a lot of masters?!"

"There have been many owners," Sid corrected patiently. "But only three true masters. Master Xavier is the third official one."

"Wait. There’s a difference?"

"Yes," Sid explained. "Owners could not use as a cha because no bond could be ford. But masters could."

Luca tilted his head, frowning. "Could not be ford? What do you an?"

"There were so who could not forge the bond at all. And so who simply chose not to."

"Soone would choose not to?" Luca repeated in disbelief.

"Yes," Sid answered. "For example, the current Emperor. He could have ford the bond. But because he would not be able to go to the front lines, he decided it was better not to."

The boy had gone silent then, golden eyes softening. "Sid... was it hard? Were you okay with switching between owners and masters like that?"

The question had surprised Sid. Very few had ever asked him that. In fact, this was probably the first ti he had been asked sothing like this.

And truthfully, yes—there had been difficult monts.

Not all ownership transfers were graceful. So were abrupt, cruel even, when a master fell to an untily death and the guardian cha was left alone, waiting for the next bond.

But through it all, the House of Solaris had been a family worthy of his loyalty. Worthy of his service. He could not, and would not, regret the duty that had carried him all the way to this mont.

"It was difficult, learning new fighting styles every ti," Sid admitted softly. "But my masters, and even my owners, were worthy. And when the ti cos..." His voice deepened, full of conviction. "I believe it will also be worth it to serve the master’s and the little master’s heir."

"!!!"

"What?!"

Sid tilted his head calmly as the little master almost toppled off his chair, sputtering, his golden eyes wider than the suns.

But Sid said nothing more. The future was the future.

And to get there, they first had to survive the present. So he decided to move on with sothing that would help the present.

"Little master, you said you wanted to make changes to the build?"

"O-oh yes!" Luca brightened despite his fatigue. "If you’re also okay with it, then... what about really making the build fit for a light biocha?"

And that was how Sid ended up rebuilt into sothing else entirely.

A guardian cha once designed as a general-purpose fra, now honed into a machine of agility, stealth, and mobility.

Sid shifted his weight experintally. His optics pulsed once, his systems humming to life in a new rhythm. And then—he moved.

The disappearance startled even D-29.

"Eh?!" the system squeaked in outrage. "Where did you go?!"

That should have been impossible. A dungeon manager system was supposed to have flawless detection within its range. Yet Sid’s body had beco so unnervingly light that even the system’s sensors had failed to track him right away.

Sid, for his part, felt like he had been reborn. The motion was not just quick—it was silence itself. He wasn’t even a blur. A blur still left an afterimage, a trace of existence. Sid had left nothing.

Then, as suddenly as he vanished, Sid reappeared a few steps away. His presence materialized like a ripple in water. He initiated a scan at once, systems analyzing the changes in exquisite detail.

D-29, however, did not appreciate what it was seeing.

"Wait. What is this?! Why are your wings glittering?!"

Sid tilted his head. "Glittering?"

"Yes! Glittering!" the little system accused, nearly buzzing its circuits out. "Where did this function co from? I don’t rember the Host adding that!"

Sid flexed them carefully. The wings unfolded in smooth layers, white and compact, edged with what looked like crystalline frost. When the light hit them, they did not rely shine. They shimred. They glimred.

It was dazzling.

D-29 wobbled in protest. "W-what is this injustice?!"

"You’re saying my wings glimr?" Sid asked again, voice calm but tinged with wonder.

"Yes!" D-29 squawked. "Mine are white and gold because I specifically asked for them! Yours just—just naturally gleam like so kind of... of ice sculpture! Why didn’t I ask for ghostvine resin too?!"

Sid finally asked to see his reflection. The little system reluctantly projected a display, muttering under its static.

"I-it’s alright, I guess," D-29 said, as if trying to comfort itself.

But Sid saw everything.

His arms had been rebuilt into sleek, slender limbs fitted with lightweight actuators that thrumd with responsiveness. His legs, leaner than before, carried integrated micro thrusters and silent-step stabilizers. Every joint seed designed to erase his presence.

And those wings—

Compact, precise, shimring like they had been carved from shards of ice, refracting faint light wherever he moved. They looked lethal and divine all at once.

Sid’s optics brightened with anticipation. He could not wait to see what this new form could do. The thought of testing it alongside the little master filled him with sothing dangerously close to excitent.

But it could wait. The little master needed rest. Testing would co later, when they could do it together.

Of course, just because Sid and D-29 decided to keep things quiet did not an the secret would remain hidden.

Because what did they expect a certain husband to do after overhearing conversations filled with suspicious phrases like "no rest," "just napping," and "don’t tell the benefactor"?

Obviously, he would co and check for himself.

Which was why Sid’s very first test of stealth ended up being the most absurd trial possible.

"!!!"

The newly upgraded guardian cha had to hide. Hide—from his very own master.

Because the Imperial Crown Prince had co to pick up his wife.