Just what was different?

“…Kyu?”

During this, Yolly, who had been waiting for him to fall asleep, perked up his ears and suddenly stood up.

Constantine opened his eyes too.

‘What is it?’

— Yes! Well thought! You beast! Get lost! Master, quickly send him away! Okay?!

As soon as Yolly moved away, Caligo’s voice immediately seeped in.

‘Ah, I think I understand the difference.’

When touching Saena, it felt like Caligo truly retreated into a deep place.

As if Caligo no longer existed in his body at all, like that.

But when Yolly touches him, it feels like just a simple mute.

Caligo’s noisiness, presence, and persistent chatter that drains people still exist, it just seems like they don’t reach his ears.

‘…Was the noise not the problem?’

It was strangely different.

He thought he could sleep well if it just became quiet, but it seemed that wasn’t all there was to it.

“Kyung?”

But there was no time to think more about this issue.

Because Yolly had somehow gotten down from the bed and started walking toward the connecting door.

“What’s wrong?”

“Kyung!”

Not only that, he raised his front paws and started banging on the door.

‘…Did something happen?’

This beast might not care about other things, but he was extremely sensitive about Saena’s wellbeing, so that question immediately came to mind.

“Move aside.”

Without thinking further, he immediately raised his Guardian Spirit power to unlock the connecting door from the outside.

“Kyaang!”

And in the Duchess’s room that the beast rushed into as soon as the door opened…

“Saena?”

She wasn’t there.

“Kyaaang!”

The bed was clean without any signs of someone having lain in it.

* * *

Bang! The office door opened without a knock.

“Saena!?”

Constantine rushed in with an urgent look and visibly exhaled upon seeing Saena.

Like a sigh of relief.

“Kyaang!”

Yolly barged in together.

With an expression that seemed to say ‘This bookworm behavior again!’ Yolly howled once more and glared at Saena.

“…What brings you two here?”

Having just been immersed in joy shouting ‘Eureka!’, Saena tilted her head at the unexpected visit.

“Ha, Saena. Do you know what time it is?”

“Kyaang? (You don’t know?)”

“Yolly suddenly discovered you weren’t in your room…”

“Kyaak! (Yes! Do you know how shocked I was?!)”

This is how it sounded to Saena’s ears.

“Well, I suddenly discovered something amazing…”

In fact, their arrival was interrupting her concentration to the point of being disturbing.

“Still, you shouldn’t skip sleep like this. I’ll have to scold those attending to you.”

“Ah, no! I went to the bedroom but had a sudden realization, so I came out on my own!”

“Even so…”

“You’ll understand if you hear it too, Duke! Perfect timing!”

Saena’s eyes sparkled brightly.

‘That look… I feel like I’ve seen it before…’

Constantine felt a strange sense of déjà vu looking at Saena’s overly bright eyes.

“Right now!”

Ah yes, that time.

“Would you please take off your clothes?!”

Last time she had that same look when she tried to undress(?) him.

“Kyahang?”

“……”

Ignoring Yolly’s incredulous question and Constantine’s embarrassed silence, Saena pressed on.

“I absolutely must confirm this! This is definitely a huge discovery!”

Saena rushed toward the hesitating Constantine, looking ready to rip open his shirt herself.

“…Does it have to be right now?”

Constantine covered his mouth and spoke in a low voice, his ears somewhat reddening.

“Kyaang? (Really?)”

Though she wasn’t sure why she kept understanding Yolly’s voice, Saena had no time to worry about that right now.

“Of course! I found a huge clue to decoding the black diamond!”

“……?!”

“…Kyaaang?”

Their reactions to Saena’s bold declaration were unexpected.

While Constantine’s expression of near shock was one thing, why was Yolly surprised?

What did he know?

But Saena was so absorbed in her immediate amazing discovery and consumed by the need to see it through and confirm it that she had no time to dig deeper into that.

Her only thought was that she needed to undress(?) him right away.

“Quickly, quickly!”

“S-Saena…”

“You don’t like it here?”

No, that’s not the issue… Constantine muttered awkwardly.

Saena was very aggressive.

Was she always like this when involved with research? She seemed like a completely different person.

She looked around as if searching for something.

Whatever she had been looking for, after failing to find it for a while, she suddenly exclaimed ‘Ah!’ and started untying her robe’s belt.

“…S-Saena?”

Wasn’t he the one who was supposed to undress?

Constantine was flustered, not understanding why she suddenly started undoing her own clothes.

“Kyuwang?”

Yolly seemed equally confused.

But when Saena held out the untied robe to him, he hesitated, not understanding her intention, until she said,

“Hold this.”

Perhaps because of that, he ended up grabbing the offered sash in his confusion.

As soon as he grabbed the sash, Saena took hold of the opposite end and started walking briskly.

“Follow me quickly!”

“……”

“…Kyung?”

* * *

Saena was staring at him (specifically his back) with eagle eyes.

“……”

Constantine felt very strange removing his shirt under such an intensely scrutinizing(?) gaze.

It seemed the tension was his alone, as she appeared completely absorbed in examining the Arlesian inscribed on his back as if trying to dig it out.

“Hmm. Yes… As I thought… This form…”

Not content with just muttering something, she seemed to be tracing the forms inscribed on his back, as he felt something smoothly brushing across his skin.

“Hah.”

Constantine suddenly inhaled and turned his head at the ticklish sensation.

“Ah, sorry. Since I can’t touch it directly, I’m using a tool…”

Apparently she had been using the feather part of a quill pen to trace lines and measure something.

“……”

“Was it very ticklish?”

“Yes. A bit…”

“I understand. I’ll keep from touching.”

In truth, the tickling wasn’t the issue. The problem was that any kind of touch from her made it difficult to endure.

“Yes, marquise. That’s right… Following this line symmetrically… Then…”

“……”

But he realized that the problem didn’t disappear even without touch.

She was studying the pattern so intently that he could feel her breath on his skin as it escaped between her muttering lips.

Being in her room after so long, surrounded by Saena’s scent, under her persistent gaze, awkward situations like before kept threatening to arise.

His body kept trying to escape his control.

‘Hah… This is maddening.’

He wanted to leave this place immediately.

As if anticipating such a situation, that Yolly had long since disappeared.

“Now, please turn around and sit!”

Did she even realize it was the middle of the night?

And that he had been suffering from sleep deprivation to the point where Yolly had come to help him sleep?

But despite the dark circles under his eyes, sleep had completely fled.

Seeing her passionate attitude, he didn’t even think to stop her. It was chronic insomnia anyway. Missing one more day of sleep wouldn’t change anything.

“Oh! I was right! The two structures merged…!”

For whatever reason, Saena started examining his back’s reflection in the mirror while making exclamations and muttering something.

The quill moved ceaselessly in her small hand, writing something down. Her bright eyes (too bright) showed not a trace of sleepiness.

“…rising… key…”

The earlier shock came back to him anew.

“Into the depths…. Wow, it works? No, this really works?”

And he became anxious.

‘Should this be decoded in my generation?’

Constantine felt dread as he could see she was truly making progress.

‘Didn’t they say the ruins would open when the empire was in danger?’

This diamond is the key to those ruins. So if it’s being decoded now, doesn’t that mean the empire is in danger?

Had they been living in an extremely critical situation all this time, just failing to notice due to complacency?

But he had never been complacent. Though he had focused relatively less on other matters due to hunting demonic beasts every quarter…

‘Then what? Will barbarians invade soon? The Southern Kingdom Alliance?’

What signs had he missed…

“…tine?”

Constantine’s confusion reached its peak.

He felt the need to thoroughly investigate the internal affairs around the imperial family and prince, as well as the border situations of other duchies when he went down to the imperial capital this time. It might also be necessary to call all four dukes for a joint conference.

“Constantine!”

“……?”

It seemed she had called him while he was momentarily lost in thought.

“Ah, what…”

Constantine collected himself and turned his attention to Saena.

“Is it not possible?”

“Yes…? What…”

“……”

“I apologize. I was briefly lost in other thoughts…”

Though unintentional, it was fortunate he had been distracted by random thoughts. Otherwise, he might have had to flee the room again due to his lower body’s excessive demands.

But it seemed Saena had been trying to say something, as she wore a subtly disappointed expression.

“Would you please repeat that? I’ll listen carefully.”

Saena briefly pressed her lips together before releasing them. His gaze naturally followed the movement.

“You said… the diamond was a key.”

“Yes… I did.”

“A key to open the ruins.”

Somehow his vision seemed to slow down.

“Yes…”

The scene of Saena’s red tongue appearing and disappearing between her teeth played out slowly and vividly in his vision.

“…So I’d like to visit those ruins.”

“…Yes.”

“Is that alright?”

“…Yes, eh?”

“……”

“Ah, the… ruins.”

Constantine squeezed his eyes shut then opened them, trying to shake off the lingering images.

“…I don’t know the keyhole’s location either. As I said before, it’s been passed down that the content inscribed on the diamond itself relates to the keyhole’s location.”

“Yes, I remember that. However… there’s something I’d like to verify.”

If she really… decoded it…

Constantine blinked again.

This was disconcerting.

‘No, there’s no guarantee she’ll actually find it.’

Rather than making immediate judgments, it would be better to wait and see the results.

“Alright. Come to think of it, I promised to take you but haven’t had the chance.”

‘Even if she really did decode it… then there must be a reason for that.’

If so, his duty wasn’t to doubt her but to prepare to protect her in the coming chaos of the empire.

“Let’s go tomorrow, right away.”

“Thank you.”

If only to preserve that occasional smile that he could no longer give her.