A Mastermind? No, I'm just the Live-In Son-in-Law-Chapter 155: The Gem Eye

“...My Lady, it’s a trap.”

“......”

“You don’t have to worry about me. Just cast me aside.”

Though my attention had been fixed on the letter for a while, I finally turned my head toward the Lady and whispered in a low voice.

“Are you really not concerned, Whitney Ringaarden?”

But somehow, as if he’d heard that tiny whisper, the Duke of Embergreen pierced into the silence between us with a sharp voice.

“The seal could be forged. Or the letter’s contents could’ve been swapped.”

“...Despite the seal and binding spell? If that were possible, the Empire’s entire postal system would’ve collapsed long ago.”

“Well, nothing in the world is truly impossible.”

To be fair, the Duke was right. In a world where magic has evolved over thousands of years, there’s no way information security wouldn’t have kept up. Binding spells aside, I do know someone who could forge a seal.

But that person is currently sitting in my office at the mansion, diligently handling paperwork and overseeing business in my stead.

Of course, it’s not like Parsha is the only person in the world capable of such eccentric feats—but someone like the Duke of Embergreen, now living as an exile, shouldn’t be able to obtain help from such people.

Still... how did the Duke get hold of that letter?

“The Count of Ringaarden and I go back quite a ways.”

“...What?”

“We weren’t friends, exactly. Hmm, how should I put it...”

As if reading my thoughts, the Duke curled his lips into a cold smile—so eerily familiar to someone else—and began speaking of my father.

“Let’s call it... antagonistic acquaintances.”

“I don’t know what game you’re playing...”

“But you, you’re not much like your father.”

Sensing something off, Meredia tried to cut in, but the Duke continued without pause.

“No, you resemble your mother much more.”

“......!”

“Especially those eyes. They’re practically identical.”

At that, I nearly blurted out: What do you know about my mother?

But I stopped myself. That had to be exactly the kind of reaction the Duke was aiming for.

So instead, I just stared at him silently.

“Do people often misunderstand you?”

“......”

“Haha. She used to be the same—always avoided, even when saying nothing, because she gave people an uneasy feeling. But...”

It was right then, just as he began sharing oddly specific details no one but a true acquaintance could know—

“...Knights, fall back.”

The Lady suddenly ordered the knights to retreat and stepped forward, speaking with urgency.

“If you came just to deliver a letter, then hand it over and leave.”

“...I’m afraid I can’t do that.”

Though the Lady no longer {N•o•v•e•l•i•g•h•t} hid the killing intent surging off her in waves, the Duke replied with unsettling composure.

“Did I not teach you to treat important guests with proper courtesy?”

“......”

“If you truly are acting Head of House, shouldn’t you at least show basic hospitality to a guest who came a long way?”

At that, the Lady wore the kind of face one makes upon hearing complete nonsense.

“If that’s how you feel, then I suppose I have no choice.”

“...Wait.”

“If I was entrusted with the letter, then surely I have the right to withhold its delivery.”

The Duke pulled a silver mana-lighter from his pocket and brought it close to the letter. Gritting her teeth, Meredia finally let out a sigh.

“Fine. I’ll receive you as a guest—just put that thing away.”

“...Hmm. Really now?”

“Yes. I’ll at least offer the minimum level of respect.”

Naturally, I was startled by her decision and moved toward her, but she turned her head slightly and shook it gently.

“There we go. That’s how you should’ve responded from the start.”

The Duke, watching silently, finally tucked the letter back into his coat and began walking confidently.

“Well then, let’s see how the estate has changed with my own two eyes... ah, wait. It’s not two anymore, is it.”

“......”

“...Anyway.”

As he rubbed the spot where his eye had once been, he suddenly stopped right in front of me and murmured.

“To think you, of all people, would be engaged to my daughter. What a trick of fate.”

“...What do you mean by that?”

“Haha, never mind.”

Leaving that cryptic remark hanging in the air, the Duke chuckled to himself and walked on.

“I wish you both a joyful engagement.”

Watching him march proudly between the parted ranks of knights, I whispered under my breath:

“...Not that I have a choice.”

Then came a brief silence.

“Whitney.”

In the stillness, Meredia sidled up beside me and whispered softly into my ear.

“You should go back. I’ll accept the letter and send it to you later.”

“...No.”

Surprised by the rejection, she faltered for a moment, then whispered again.

“Then... how long are you planning to stay?”

“Until the Duke leaves.”

“Y-you’re not busy these days?”

“This much is fine.”

Truthfully, I had a mountain of tasks to handle right now. But if I returned to the mansion and something happened, I’d regret it forever.

“You... you don’t have to push yourself because of me.”

“......”

“I can handle this on my own... so just...”

The way this usually composed woman was now dripping cold sweat in front of me—I couldn’t possibly leave her like this.

“My Lady. What do you think the Duke’s true objective is? Surely you know he didn’t come just to deliver a letter.”

“......”

“If I’m right, his real goal is...”

Trying to calm her and assess the situation, I asked, and she finally responded in a steadier voice.

“...To reclaim the rights of Head of House.”

“That’s what I thought. But is that even possible?”

“The Gem Eye—if he gets that back, it is.”

“...I see.”

The Gem Eye—if I remembered correctly, it was a particularly unique fragment of the Demon King’s power. Unlike the scattered powers that had recently begun surfacing, the Gem Eye had appeared sporadically throughout history.

Because of this, the Gem Eye was long regarded as a symbol of absolute power and dominion.

But hearing how Meredia spoke of it, it almost sounded as if the Gem Eye could be transferred at will.

“That... sounds like a long story.”

When I pointed that out, she glanced around and finally spoke.

“I’ll explain everything in detail later, when it’s just the two of us. But what I can say is...”

And what she said next was something I’d never heard before.

“I didn’t have the Gem Eye from the beginning.”

“Then...”

“Do you know why our family is called ‘Embergreen’?”

Not knowing what to say, I tilted my head. She gave me a sidelong glance, gently touching her eye, and whispered.

“In my case... the Gem Eye was artificially implanted.”

I must’ve made a dumbfounded face, because she answered before I could even ask.

“You’re wondering whether it was my choice or someone else’s?”

“......”

“Until I got the Gem Eye, I didn’t have the power to choose anything for myself. That decision... was probably my first real choice.”

“So everything changed after you received it.”

“Yes. Though I had to give up many things in return.”

She looked quite sorrowful as she said it.

“Then... who gave you the Gem Eye?”

Trying to steer the topic elsewhere, I asked.

“...That’s...”

But her face froze the moment I did.

“...Sorry.”

“Huh?”

“That’s the one thing I can’t tell you.”

I didn’t know why, but based on the expression she wore—it was clearly her most sensitive nerve.

“...You said earlier that if the Duke regains the Gem Eye, he can reclaim Head status. Does that mean... his lost eye was the Gem Eye?”

“...Yes, that’s right.”

“So... is that eye now implanted in you?”

She didn’t answer immediately, and her face paled.

“Y-yeah. I took his eye. It’s in me now.”

“...I see.”

“A-are you satisfied now?”

Judging by her reaction, it was probably best not to mention this again in front of her.

“I didn’t mean to upset you. I just needed to prepare countermeasures.”

“...I know.”

Thankfully, she didn’t seem angry. But her hand trembled again, so I gently held it as we walked.

“Anyway, I have a plan.”

“...A plan?”

“A very effective one that can neutralize whatever the Duke is plotting.”

And with that, I began explaining—this plan I’d just come up with, one that absolutely required her permission.

“If you had a plan like that, why not suggest it earlier...”

“Grant me shared rights to House Embergreen.”

“...What?”

She blinked at me, stunned.

“Ah—not full rights. Let’s split it fifty-fifty.”

“What are you even saying...”

She looked incredulous, but then her eyes widened in realization.

“Wait—you’re not saying...”

“Let’s get married.”

“......”

“Within a week, starting today.”

It was something I’d wanted to say for a long time—but only now could I truly bring myself to say it.

‘...Because after that, I probably won’t be here anymore.’

That last part rose in my throat... and quietly sank back down again.

***

“Think about it, My Lady.”

“......”

“If you don’t think it’s the right time, I’ll accept your refusal. It’s your decision to make.”

Leaving behind a stunned Meredia frozen in place, Whitney gave a faint smile and quietly walked forward.

“......”

A silence followed.

“...Marriage, huh.”

As soon as Whitney made his declaration, the knights and servants all lowered their heads in unison, feigning ignorance. And there, muttering blankly among them, a lonely smile finally formed on Meredia’s lips.

“If I go through with it... would I selfishly get to keep you forever?”

Then, gently stroking her eye again, she whispered under her breath:

“...Even if you learned that I climbed this far... with the eye of your dead mother?”