The Regressed Son of a Duke is an Assassin

For Brian, there’s one routine in his day that’s as non-negotiable as exercise.

It’s visiting the academy’s mailroom.

As Cyan’s retainer, he checks daily for any letters or packages addressed to him, and if there is anything, he delivers it to Cyan without delay.

Given Cyan’s introverted nature, it wasn’t often that he received letters.

Except for the occasional affectionate letters from Alice, it was almost never. However, today there was a letter from someone other than Alice.

The sender’s name wasn’t written on it.

But upon checking the back of the letter, Brian’s mouth fell open in shock, and he immediately ran to the Royal Hall, where Cyan was.

The letter bore the seal of the Vert family.

“Yo- Young Master, a letter has arrived for you!”

Even as he ran, he made sure the letter was perfectly preserved without a single crease.

“……”

Cyan didn’t ask where it was sent from.

Seeing the seal on the letter, he seemed to have already deduced its origin and, as always, calmly proceeded to read its contents.

It’s been nearly three years since he became Cyan’s retainer.

By now, he had developed a keen sense of awareness.

Though he didn’t say it out loud, Brian had some idea who had sent the letter.

After all, if the seal of the Vert family was on it, it naturally meant a member of the Vert family had written it, right?

If Alice had sent the letter, it wouldn’t be packaged so luxuriously.

Wondering if it was some official document sent by the head of the family to a family member, Brian cautiously speculated.

“Ha…”

A perfect blend between a sigh and a chuckle.

His expression seemed utterly baffled at first glance.

It appeared he had read something unpleasant.

Cyan then silently stared at the letter for about ten minutes.

The atmosphere grew significantly heavier.

It felt like a serious moment that shouldn’t be interrupted carelessly, leaving Brian sweating profusely and frozen in place.

-Thud

After a moment,

Cyan casually threw the letter he had been reading onto the floor.

“I’ll be out.”

Just like that, Cyan left the room with just a single word, leaving Brian blinking in confusion at his place.

“What’s going on? What happened?”

Emily, who had been leaning against a wall and watching the situation, hurried over.

“I- I don’t really know! Maybe there was something unsettling in the letter…”

“This came from Vellias, right? If it has the seal, it must have been sent by at least the eldest son or the Duke?”

Emily now held the letter Cyan had thrown, in her hand.

“You’re planning to check it?”

“Huh? No, I mean, if he threw it away so carelessly, it might not be something important…”

Despite being curious, the thought of secretly reading the master’s letter was unimaginable to Brian.

“Please, restrain yourself, Miss Emily. It’s not appropriate for us to read it…”

“I know that! I’m aware, but…”

Even someone as lighthearted as her knew the boundaries of a maid’s duties.

However, their strong curiosity made it hard for them to look away from the letter.

“If it’s not something important, he’ll tell us later, I guess…”

Eventually, Emily gave up and neatly placed the letter back on the sofa.

The two of them forcefully curbed their curiosity and returned to their duties.

-Creak

Meanwhile, Nana, who had just woken up, opened the door and came out.

“Yaaawn!”

With a cute yawn, she naturally approached the sofa and plopped down.

Wagging her tail and rubbing her eyes, it wasn’t long before Nana noticed the letter beside her.

“……?”

About five minutes passed.

During those five minutes, Nana’s eyes didn’t stray from the letter.

“Nana, are you up…?!”

A moment later, Brian, returning to the living room, stopped in his tracks upon seeing the letter in Nana’s hands.

With wide, curious eyes, Nana tilted her head and asked,

“Papa getting married?”

* * *

[How come the face of a fresh groom seems so gloomy?]

Talking about a groom, huh.

Knowing that responding would only tire me out, I simply sighed it off.

Considering the course of events so far, I had thought this day would come eventually.

The engagement between Arin Severus, the youngest of the royal family, and Cyan Vert, the youngest of the Vert Ducal family.

Frankly, from the moment a non-royal like me was assigned to the Royal Hall at the academy, the engagement was almost certain.

It would be a lie to say I didn’t see it coming.

But isn’t this too soon?

Both the princess and I are only just thirteen.

Though it is customary among noble children to get engaged before graduating from the academy, usually at fifteen, or sixteen at the latest, engagements at such an early age are extremely rare.

Well-known to those who should know, the engagement between the royal and duke’s families is not just a matter of marrying off two individuals; it’s a promise of mutual support.

In other words, I’m to gain the title of the imperial son-in-law, and Princess Arin is to have the support of the Vert Ducal family.

Just from that, it’s clear there’s nothing good in this for me.

With this news likely already spread among the other members of the royal family, I’ll be under even closer surveillance and suspicion from now on.

There will be people sent to watch my every move, and a thorough investigation into my background will probably begin.

The more this happens, the more my movements will be restricted.

With the Emperor arranging it and my father agreeing, I had no right to refuse this engagement.

The same goes for Princess Arin.

I’ve been dragged into the worst possible mess.

For now, I decide to put that aside and focus on what needs to be resolved immediately.

The altar of Aer, located in the farthest corner of my spatial dimension, surrounded by dense fog.

It’s the dwelling of my lord, whom I haven’t visited in a while.

As I step onto the altar, the fog that had enveloped it slowly clears, revealing his form.

[Kaeram and you, it seems none who seek me ever come with a smile.]

Seeing my near stern expression, Aer commented with a tinge of regret.

“If you could create situations worth smiling about, that would be nice…”

My reply was half in earnest.

“I’m short on time, so I’ll get straight to the point. Where is it? The owner of the scripture?”

[……]

Aer hesitated to answer right away, remaining silent.

“You must have known from the beginning. And yet, you chose not to tell me or the leader. As a result, this situation has arisen…”

Aer’s eyes, which had been fixed on me with a mysterious smile, slightly shifted away.

[……]

Although he didn’t show it, I had a rough idea of where his gaze was directed.

After a moment of silence, Aer spoke with a smile, as if it was nothing significant.

[As you know, I’m an entity rejected by the divine realm. However, that doesn’t mean I’ve lost my essence as a god. Just as a human doesn’t become a beast simply because they are ostracized by other humans.]

It was a valid point.

The people I’ve killed might have been trash unworthy of being treated as humans, but their essential nature as people was something that couldn’t be changed.

It wouldn’t be any different for our exalted gods.

[There’s one rule among gods that cannot be defied from the moment of their birth.]

“A rule?”

[Yes. A god must never divulge what another god intends to do to a being other than a god. Breaking this rule doesn’t just result in ostracization.]

“What happens then?”

[They cease to exist.]

His concise and clear answer left me speechless.

My gaze naturally shifted to Kaeram standing behind.

[Even the owner of the scripture you met would be the same. The scripture, knowing of Kaeram’s existence, wouldn’t have disclosed it either.]

Now I understood why she remained silent.

The demon sword and the scripture, being akin to children born from the power of gods, should indeed be considered divine beings.

But is that really necessary?

Why would beings so exalted and seemingly fearless need to impose silence on lesser beings, to the extent of threatening their very existence with such a severe restriction?

It was something difficult for me to understand in my current state.

[Are you afraid? Afraid that your existence will be revealed by the owner of the scripture?]

I responded with silence.

It wasn’t so much fear as it was an uncomfortable feeling of concern that I couldn’t fully dismiss.

I couldn’t outright deny it.

[I understand. You’re concerned about the repercussions that revealing your identity could have on those around you.]

Was it because he hit the nail on the head?

I found myself chuckling without realizing it.

As Aer said, the revelation of my identity isn’t really a problem for me.

After all, it’s not like the world can kill me because of it.

But at some point, I started to have more and more things around me that I needed to protect.

For an assassin, who should prioritize his own life above all else, having others to protect is no laughing matter.

Wasn’t I the one who vowed to live for myself, breaking away from a life lived for others?

I don’t want to bother with pathetic denials.

Unlike my previous life, where I focused only on that one demonic being, now I find there’s too much I want to hold in my two hands.

What’s there to worry about or make a problem of?

Protecting them is what matters to me, and if there are beings that threaten that, I simply have to find and kill them all.

Whether they are human or divine.

[Looking at those eyes, I wouldn’t dare face you. It seems you’re ready to kill even a god.]

Aer clicked his tongue as he looked at me.

“So, to sum it up, you’re not planning to tell me, right?”

It’s not so much that he won’t tell me, but rather that he can’t.

In the end, it means I have to find out for myself, so there’s no point in pestering him any further.

I turned to leave.

[The more you have to protect, the more enemies you will face. The owner of the scripture likely thinks the same.]

“What do you mean?”

[It means you should create allies who can help you.]

Turning back to face him, Aer had a mysterious expression on his face.

As if he was about to make a suggestion.

[Why not try finding the Grimoire?]

(To be continued)