‘Wait a second...’

Yakseon’s sudden shift in attitude—and the way his eyes sparkled while staring at the kids—

The moment I saw that, a terrifying thought hit me.

Yakseon—he was someone who made medicine. And in the eyes of people like that, what would our kids look like?

I leapt forward and blocked the children from view.

‘This is insane!’

When I’d first met my father-in-law and the Heavenly Poison Deity, they had come all the way to Hainan Island to catch the mother of the kids—Fabre’s mate—so they could obtain her Neidan for Hwa-eun’s treatment.

Technically, what they needed was just the Neidan, but I’d heard that they’d planned to use the rest of the body too. The shell was going to be used to craft tools, and the flesh was going to be dried and processed into medicinal materials.

But once Cho, Hyang, and Bini made it to the Tang Clan and received affection, no one could bring themselves to use their mother’s body. Instead, it was sealed inside the Hall of Ten Thousand Poisons.

Even giving her a burial was tricky. Because spirit beast bodies are treated like priceless treasure, they were afraid it might get stolen. That’s why she was sealed in a stone coffin inside the hall.

Of course, using her was forbidden.

The Tang Clan might be a top-tier family when it came to making poison by soaking people in venom, but they weren’t heartless enough to turn the kids’ mother into medicine or tools.

In fact, they even built a shrine in front of the sealed room, offering regular rites in gratitude for saving Hwa-eun’s life.

And when one studies poison in the Tang Clan, there's something you always learn along with it—the efficacy of poisons and venomous creatures.

While I paid attention to their behavior and ecosystems, the Tang Clan focused on their properties and how to use them. Specifically, what kind of toxicity they produced in humans and where they could be used medicinally.

Nothing too advanced—just general knowledge like which organ it affects, or how it might help.

From the little I picked up, I remembered that centipedes were known to relieve spasms and had antitetanus and analgesic properties. Apparently, they were widely used.

A common tale was that when children had seizures—what they called gyeonggan—you could brush the froth from their lips with powdered centipede, and they’d recover.

Based on all that, it was clear that in this era, the body of an O-gong, especially a spirit beast O-gong, would be considered an incredibly precious medicinal resource.

So the sparkle in Yakseon’s eyes definitely looked like he’d found a treasure trove of rare medicinal ingredients.

‘If he says even one wrong word, I don’t care if he’s Hwa-eun’s friend—I won’t let it slide!’

If he so much as thought about using my kids as medicine, then no connection to Hwa-eun would protect him.

With determination blazing in my eyes, I shielded the kids. Hwa-eun tilted her head, confused.

“So-ryong, what’s going on?”

Then Yakseon finally opened his mouth.

“No, I think there’s been a bit of a misunderstanding...”

“That’s not allowed!”

I didn’t even let him finish. I cut him off sharply.

The kids flinched in surprise at my sudden shout.

—Tsrut? 『Daddy, what’s wrong?』

—Tsruruu? 『Daddy?』

Then Yakseon’s voice came again.

“I see you’ve misunderstood something. But it’s not what you think. Not at all.”

“It’s not?”

“No. Why don’t we sit down and talk for a bit? You said we’re standing on top of that giant turtle, right? If I’m right... I might be able to treat him.”

“You can treat him?”

Sure, the Immortal of Medicine had said his disciple could handle it—but when Yakseon actually saw Elder Geumdo, he’d looked anything but confident.

At the time I’d figured he was just surprised by how big the turtle was, but now it seemed like there was more to it.

Now that he’d seen the kids, he was saying he could treat him. That made it worth hearing him out.

“Yes. Honestly, before I saw your kids, I thought it might be too difficult—even for me. But with those children around, it might be possible. Of course, it’s not what you think.

Hwa-eun sees them as daughters, which makes them granddaughters to me, doesn’t it?”

“...Fine. Got it.”

His eyes still didn’t sit right with me, but if he really could cure Elder Geumdo, I couldn’t just ignore that. So I sat down on the bamboo mat.

Once I did, Hyang climbed onto my head, and Cho and Bini rested on my shoulders, watching Yakseon closely.

Meanwhile, the Immortal of Medicine, Hwa-eun, and Sister Seol all had that what in the world is going on? expression on their faces.

While Hwa-eun brewed some tea, Yakseon gave an awkward smile and asked:

“You reacted that way because you thought I saw those children as medicine, didn’t you?”

“Well... yeah.”

—Tsrut!?

—Chu!?

The kids gasped, startled by Yakseon’s blunt words.

Hyang let out a warning chirp as she glared at him.

—Tsruruuu! 『Dad, can I bite him just a little?!』

It was one of those “mess with me and I’ll chomp you” kinds of chirps. Yakseon smiled and raised a hand gently.

“I heard they understood human speech, and now I see it’s true. Don’t worry. I absolutely don’t mean anything like that.

If Hwa-eun considers them her daughters, then they’re granddaughters to me.

I’m not such a bad old man, you know.”

Yakseon was smiling kindly as he spoke, but... his eyes—those sparkling, lucid eyes—looked like something you’d see in a madman.

So naturally, neither I nor the kids dropped our guard.

Then he tapped the bamboo floor lightly and said:

“To clear up this misunderstanding, I should explain the situation with this turtle first.

You said the giant turtle’s illness started in the back, with the inflammation and pus eventually spreading to the lungs and causing pneumonia, correct?”

“That’s right.”

“Yes, exactly.”

At our responses, Yakseon nodded and continued.

“My brother here seems to think I can cure it with medicine, but there’s a problem.”

“A problem?”

“Yes. My brother uses acupuncture and moxibustion, so he doesn’t know—but when it comes to medicine, you have to be incredibly cautious.

Even with humans, the same medicine can be poisonous depending on the person’s constitution. Things vary based on weight and gender, too.

So if it’s already tricky for humans, what do you think it’s like for a turtle? A giant turtle, at that? Before we give any new medicine to people, we test it on animals—and what we’ve learned is that what’s harmless to animals can still be toxic to humans.

So the reverse must also be true.”

‘Hoooh...’

This translation is the intellectual property of Novelight.

Yakseon wasn’t just some back-alley quack.

He knew about allergic reactions and how things harmless to animals could be harmful to humans—concepts you'd only know from advanced medical understanding.

These were ideas that only existed in my previous life’s medicine. Yet somehow, he had an intuitive grasp of them.

“I actually know what substances are poisonous to turtles,” I said.

At least one of his concerns, I could help resolve.

Turtles are particularly vulnerable to oxalates and persin.

Oxalates are found in foods like spinach and beets, and persin is found in plants like avocados.

Avoiding just those two would make most treatments safe.

But Yakseon wagged a finger and said:

“Oh? Really? That’s very interesting. But let’s set that aside for now. That’s not the main issue.

The biggest problem here is the turtle’s size. To treat something this massive, we’d need an enormous amount of medicinal ingredients—and it would be extremely difficult to prepare.

Just think about it. If we were to make a pill strong enough to affect this turtle, how large would that pill have to be?

And since human medicine might not even work on a turtle, we can’t know for sure. I’ve never treated a patient like this before.”

That was the expert talking—and everything he said made sense.

When prescribing medicine, precision matters.

Even in my previous life, dosage depended on body weight, and timing had to be carefully controlled.

“But earlier, you said you might be able to cure him?”

I pressed again, and Yakseon nodded.

“Tell me, how much do you know about O-gong venom?”

“About O-gong venom?”

“Yes. You see, poison and medicine are often the same substance. It all depends on how and where you use it.

I’ve spent the last ten years researching how to use O-gong venom as a medicine. And I’ve discovered that it can be medicinal.”

In my past life, too, centipede venom was a promising subject of study.

The venom typically contains tyrosine, cholesterin, leucine, formic acid, and peptides similar to those found in bee venom.

Some of these components, when introduced into the human body, interact with specific sodium ion channels—especially those that block pain—resulting in a powerful analgesic effect.

It was stronger than morphine, without the addictive side effects.

That was the potential of centipede venom.

Some studies had even shown it could trigger apoptosis in cancer cells and had strong antimicrobial properties—strong enough to kill tuberculosis bacteria.

Though I’d known all this, I’d never thought to isolate those compounds myself—because I had no way of extracting them.

But now, hearing Yakseon speak, a glimmer of hope rose within me.

‘Could it be...?’

I looked at him with wide eyes, and he continued.

“I discovered that centipede venom is very effective against inflammation and pus—especially in cases of pulmonary wasting diseases. It also relieves pain rapidly.”

“Pulmonary wasting?”

“A coughing illness where the patient eventually coughs up blood and dies.”

‘Whoa! He figured out its antibacterial properties?!’

I’d read about that in medical journals in my past life. The fact that he figured it out—on his own—in such a backward medical environment?

If he lived in my past life, Yakseon would’ve been a Nobel Prize contender.

While I was still in awe of his findings, he looked at the kids and said:

“But the centipedes I used didn’t have enough venom—or their medicinal strength was too weak. I would’ve needed thousands of them to extract enough.

That’s why I was about to give up on using centipede venom altogether. But with your children, I think I could get enough.

Would you be willing to share some venom?

If it’s similar to ordinary centipede venom, I think it could definitely help the turtle.”

Of course, if it was just venom—not body parts—I had no problem offering it.

“For that reason, of course. But... I’m not sure if their venom will work. It’s not quite the same as regular O-gong venom.”

“Different, you say?”

“Yes. This one here is Cho, this one’s Hyang, and this one’s Bini...”

Cho’s venom is highly acidic, almost like hydrochloric acid—dissolves proteins. Hyang’s venom, as you know, is a flame-type venom that makes blood burn.

‘And Bini...’

I glanced at Bini as I spoke.

Her venom emerged like tear gas in a mist, and she did have fangs capable of delivering it—but the venom itself didn’t seem particularly strong.

Still, if any of them had a chance of being similar to typical centipede venom, it was her.

“Now that I think about it, Bini’s venom ✪ Nоvеlіgһt ✪ (Official version) might be the most promising...”

“Promising?”

“Yes, Elder. As I said, Cho’s venom melts flesh, Hyang’s burns blood... but Bini’s venom doesn’t seem to have any extreme effects. It’s stronger than an ordinary centipede’s, of course, but chemically, it might be the closest.”

“Ooh! Really?”

Yakseon’s face lit up with joy.

Then he turned to Bini and said, unable to hide his excitement:

“Would you mind spitting for this old man?”

—Tsrut?

‘Elder... I think you mean venom, not saliva. Also, could you not phrase it like that?’

Bini clearly sensed the unhinged glint in Yakseon’s eyes. She trembled and quickly ducked behind me.

—Tsruruu... 『Daddy... that old man’s scary...』

Our Bini is no coward—she’s got guts. But this time, she was clearly afraid.