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I poured liquefied Reivaskin, an alchemical metal, into the engraved grooves of the Ithildin-Dumanium composite that Melua had carved with the Spark Shot simplified formulas, then dried it using the warm air from a magic dryer.

Once that was finished, I assembled the four completed plates into a barrel and welded the seams together with the heat pen.

The result was a long, rectangular barrel.

At this point, it was essentially complete.

I fitted the grip I had prepared beforehand onto the barrel and tested how it felt in my hand. I had used parts from a standard magic cannon as the base so that it would be comfortable for Marie to handle, and the fit was excellent.

I inserted Blood Grail, the aether amplifier, into the recessed compartment in the grip and secured it in place with metal fittings.

With that, the custom-made magic cannon incorporating every one of Marie’s requests was complete.

“…It’s finished. We actually finished it.”

Melua, who had watched the assembly with bated breath, let out an awestruck whisper.

“Congratulations, Melua.”

I held the completed weapon out to her by the grip.

Her eyes glistened as she carefully accepted the magic cannon and hugged it close.

“Thank you… But this is almost entirely thanks to you, Master!”
“No, no. You’re the one who patiently engraved the simplified formulas that made the whole thing possible.”

It wasn’t that I couldn’t have done it myself.

But the fact that Melua had overcome something she struggled with—for Marie’s sake—was a tremendous step forward.

In fact, seeing how smoothly the liquid Reivaskin had flowed through every engraved channel made it obvious just how carefully and precisely she had worked.

“I’m happy to be praised. Thank you… But… but! This mechanism only works because of your Blood Grail, Master! …Still… thank you. Thanks to you, it’ll be ready in time for Marie’s birthday!”
“That’s what matters.”

I was relieved that Melua understood I genuinely meant my praise.

The way she instinctively tried to downplay her own accomplishments was, somehow, a reassuring reminder of what a kind person she was.

“Hey, since we’ve gone to all this trouble… could I ask you to give it a cool name, Master?”
“I think you should be the one to name it. Haven’t you been thinking about one?”

After all, she had spent an entire year coming up with ideas to make this possible.

It was hard to believe she hadn’t thought of a name as well.

“…Mmm… Whenever I try, it just doesn’t feel right. I’m not really good at naming things, so I’d rather leave it to your sense of style—”
“Melua.”

Ah.

Perhaps she was holding back out of consideration for me.

If that was the case, then as her master, that was exactly what I didn’t want. I never wanted my disciple to feel she had to hesitate around me.

“Who is this gift from, and who is it for?”

As I wondered how best to persuade her, Alfe’s face came to mind.

She probably would have said something like this.

What mattered about a gift was who wanted to give it to whom.

No matter who had helped make it, the feelings of the giver were what deserved to be cherished.

Melua might have been worried about it, but that held true even for a gift created through alchemy.

“It’s… from me to Marie. I know that…”
“Then you already know the answer.”

I spoke gently, as if guiding her to it.

Melua lowered her head in resignation.

“…Promise you won’t laugh. I was thinking of calling it Vesper…”
“That’s a wonderful name, Melua. May I ask what inspired it?”
“Well… it’s not really an inspiration so much as… You see, to me, Estea is the Morning Star. Venus shining brightest at dawn, the light that cuts through the darkness and leads everyone toward daybreak. And Marie is the Evening Star—the same Venus, shining brightest in the night sky. Even in the darkness, she’s a beacon that guides Estea. I want Marie to keep supporting Estea together with me from now on too. So… I wanted the name Vesper to express my admiration for her.”

Though she stumbled over her words, Melua carefully explained the meaning behind the name.

Now that I knew about her past—and about the bond the three of them shared—I understood her feelings immediately.

“It suits Marie perfectly.”
“Right? Well… she’s not exactly the elegant, quietly supportive type. She’s more the kind who charges straight in.”

In that case, it suits her even better. A magic cannon that compressed lightning aether instead of firing bullets seemed like the perfect weapon for Marie.

I wanted to test-fire it.

But wasting such a precious first shot ourselves would be a shame.

I’d much rather show it to Marie as soon as possible…

And see the look on her face.

“…So, what do we do now? Should we give it directly to Marie?”
“No, no, no. It is a firearm, after all. We got permission to build it on campus, but that was a year ago… Now that it’s finished, I think we’d better report it and get permission to carry and use it.”

Ah.

So it was expected to be used on academy grounds as well.

Since the aether amplifier used Blood Grail made from my own blood, the places and situations where it could actually be used would be quite limited.

“Then let’s submit the application. I’ll help.”
“It isn’t really enough work to call it helping, but… we’ll have to go see the Professor. I think it’d be easier if you came with me, Master.”

Melua’s unexpected answer made me tilt my head.

After all, she’d known the Professor much longer than I had, and the two of them were surely much closer.

“Really?”
“It’s not that I’m nervous or anything. It’s just… this magic cannon—Vesper—turned out really well. The Professor’s definitely going to start asking questions.”
“Ah… yes, I suppose that’s true.”

Especially since it incorporated Blood Grail, it was almost certain to pique the Professor’s interest in aether amplification.

If the questions became too technical, having me there would probably make Melua feel a little more at ease.