A Mastermind? No, I'm just the Live-In Son-in-Law

That very man was now calmly wiping the blood from the corner of his lips and speaking in a soft voice to the person who had just poisoned him.

“Imagine the scandal, had people started to say the noble lady tried to poison me.”

If anyone, even for a moment, had seen the eerie smile on his lips, it would’ve sent a chill down their spine.

And at that moment, Merdia realized.

The boy standing before her, radiating danger, might be the same kind of person as her.

‘The benevolent noble lady would never do such a thing, of course.’

No... he might even be worse than her.

“Isn’t that right, Lady Merdia?”

And it seemed she had just walked straight into his trap.

“So, could you please stop looking at me like that?”

As if he knew exactly what she was thinking, he narrowed his already narrow eyes even further, giving her a look as if she were prey caught in a trap.

“It’s scary, you know, that expression.”

The expression that should’ve been on his face... was now slowly settling into her own.

For the first time, Merdia, the hunter, found herself in the shoes of the hunted.

***

Whitney Lingarden.

Eldest son of the Lingarden family, a humble house of counts near the capital of the Empire.

He had never done anything truly wrong in his entire life. Yet, thanks to his suspicious appearance and misleading speech, he had unintentionally accumulated a long and embarrassing history.

Now, staring at the platinum-blonde noble lady who once had been his favorite character—but now was very much alive and threatening him in real life—he was calmly organizing his thoughts.

‘...She’s seriously terrifying.’

The only way to escape his now thoroughly twisted fate was to save this dreadful villainess from her inevitable ruin.

He believed it wasn’t a coincidence he regained memories of his past life just moments ago. Perhaps a divine force was lending him a hand.

“Well then, shall we return to our previous discussion?”

He forced himself to smile, drawing upon every last drop of courage he had.

“We still have a lot to talk about, don’t we?”

***

It seems I’m living my second life.

I realized it the moment I lifted the teacup during my first meeting with my newly assigned fiancée—an engagement arranged just one day prior—and woke up moments later, having collapsed.

‘...Rather than picking up where we left off, maybe we should first check your condition.’

“Hm.”

“We urgently need to investigate how poison ended up in the tea. So, we’ll have to postpone our conversation for now.”

Once I acknowledged that, the face of my awkwardly silent fiancée began to look oddly familiar.

Amidst the panicking maids, only one person stood calmly, her gemstone-like eyes fixed on me.

She was none other than Merdia Embergreen—the sole heir of the Empire’s ducal house.

And according to the memories that just returned to me, she was the main villainess of Blacktail Fantasy 3, who appeared as the final boss in nearly every route.

“But that expression of yours... what is it supposed to mean?”

No matter the route, she always met a tragic end.

And because of that, I had stayed up countless nights trying to save her—my absolute favorite character.

“Do you have a problem with my proposal?”

Now, that very character stood before me, alive and breathing.

The poison in my teacup was just a bonus.

This translation is the intellectual property of Novelight.

“You vomited blood and collapsed... of course you must feel unwell.”

“I’ve called for the court physician. If you come with us now, we’ll have you examined immediately...”

I was quietly organizing my thoughts, eyes closed, when I heard the flustered voices of the maids beside me.

Well, it’s not just me who should be shocked.

They were the ones who had to witness a man nearly die, suddenly revive, and then act like nothing happened.

As far as I know, Whitney Lingarden—my current identity—is nothing more than an annoying obstacle in Merdia’s grand plan.

But from what I recall, they didn’t intend to kill me. They were just trying to scare me with some sleeping poison.

Now that I’ve woken up, they’ll probably use “treatment” as an excuse to drag me somewhere secluded and try to intimidate me.

Still, no matter how terrifying Merdia might be, I have no intention of doing as she says.

No—I'll do everything in my power to survive this bad ending.

Even if it means staying by the side of the villainess Merdia herself.

The reason was simple.

It wasn’t just because I felt sorry for her.

If this engagement fell apart, my own fate would go up in smoke as well.

The Lingarden family, which I currently belong to, may look fine on the outside, but it’s hanging by a thread both internally and externally.

If the engagement with Merdia were to break off, it’s likely we wouldn’t last a few more years.

We’d end up as fallen nobles—or worse, homeless in the streets.

That’s why this engagement had to succeed—not for the sake of the family’s prestige, but for my own survival.

No matter what people said about her reputation, the fact remained: being engaged to the sole daughter of the Empire’s only ducal house was an advantage that no one could ignore.

Honestly, my memories had just awakened, so everything still felt awkward. I wasn’t even sure if I could pull this off.

The only silver lining was that my personality and temperament hadn’t changed at all from my previous life to this one. I was still me.

So let’s take comfort in that. I’ve set a goal, so now I just have to do everything I can to achieve it.

The first thing I had to do was clear.

I had to let her know—without saying it outright—that someone had tampered with her plan from the start, trying to actually kill me.

There were eyes and ears everywhere, so I couldn’t say it directly, but Merdia was smart. With a little hint, she’d understand.

“I promise the ducal house will investigate this matter thoroughly. For now, I’ll take my leave—”

“Please wait a moment.”

I really hoped this little performance of mine would prove that I was useful, that I wasn’t just some deadweight—and above all, that I was on her side.

“I’d like to show you something useful I can do.”

...But if she just brushed me off and told me to go home because she wasn’t interested, what was I supposed to do then?

That... would be a problem.

***

“Something interesting...?”

“I’m certain it will pique your interest, Lady Merdia.”

Even before Whitney opened his eyes again, Merdia had had no doubt that her plan would go off without a hitch.

She was someone who took it for granted that the world would move according to her will.

So it was only natural that the current situation felt especially unpleasant—and downright humiliating—for her.

“If you don’t want to see it...”

“Oh dear. That would be unfortunate.”

The eldest son of the Lingarden Count family, who should have already been unconscious and carried out by the staff she had prepared ★ 𝐍𝐨𝐯𝐞𝐥𝐢𝐠𝐡𝐭 ★ in advance, was instead sitting there calmly, leisurely holding a teacup.

Speaking as though he’d known everything that was going to happen here today, wearing that irritating smile that made even the composed noble lady flinch.

“If you really thought this would go your way, then you’ve underestimated the ducal house.”

“Ah, I wasn’t referring to you, Lady Merdia. I meant me.”

Her brows furrowed at his blatantly provocative tone. But his response was so ridiculous, she could hardly believe her ears.

“Just like you said, why would you be the one getting into trouble? I’m the one who’d be in danger here.”

“Ha...”

Whitney’s tone was calm, but what he held in his hand was the teacup that Merdia had spilled.

And on the other end, Merdia’s patience was reaching its limit.

“...Well, if you put it that way, I suppose I’m curious too.”

But Merdia was not someone who would show weakness or fall apart over something so trivial.

In fact, Whitney didn’t know this, but the teacup he was holding had already lost its value as evidence.

The terrifying poison she had crafted—her own masterpiece—was the result of countless layers of trial and error.

It was designed so that, after a certain amount of time, no matter what method was used, the poison would become undetectable.

So whatever “interesting thing” he planned to show her, there was no way it would prove her crime today.

‘And even if he does somehow uncover the truth... it’s not a problem.’

Of course, considering who he was, it would take considerable skill—but even if he succeeded, nothing would change.

“Then, shall we see it?”

With that certainty in mind, she mirrored the smile of the man seated across from her.

“Haha. Thank you for giving me the chance.”

“Don’t mention it, fufu.”

Time passed.

A lot of time passed.

“Don’t tell me... this ‘interesting display’ you promised is just you sitting there doing nothing?”

Leaning on her hand and staring at him for quite some time, Merdia finally broke the silence with a cold smile.

“...If that’s it, then I must say, I’m disappointed.”

“......”

It had been a while since Whitney had confidently made his declaration.

But all he’d done since then was sit still with the teacup in hand, seemingly meditating.

If he’d attempted to detect the poison with magic, it looked like he’d failed quite miserably.

“Escort Sir Whitney to the infirmary. And—”

Silently sneering to herself, Merdia gave the signal to the attendants who had been standing by at her sides.

—Fwoooosh!!!

“...What!?”

Just as her attendants moved to drag Whitney away, black flames suddenly erupted from the teacup in his hand.

“You’d best step back.”

“That...!?”

Seeing the scene, Merdia instinctively stepped back from her seat, her eyes wide, lowering her slightly trembling right hand.

Because what was now blazing in his hand was nothing less than the manifestation of black magic.

It was a sign of a grave crime—punishable by death regardless of status or rank, even for someone of imperial blood.

Naturally, it had never been part of today’s plans to use such a material in her “small incident.”

“I could’ve died, you know.”

“...Heh.”

Apparently, this man had no intention of letting this end as a mere ‘small incident.’

“Of course, I mean me.”

“...You’re bold.”

It was the moment the trap faintly set around Merdia—finally—snapped shut.

—Though only in her thoughts.