Chapter 232.1. Shin’s Heroic Event

A purple radiance emitted from the magic circle that suddenly appeared in the hall illuminates Mii-chan and her friends.
“W-What is this?”
“M-My strength is fading away~.”
“It’s like our mana is being absorbed!”
Something seems to be leaving their bodies. Yamiyo and others kneel, wearing expressions of agony. 
My classmates also collapse to the ground as if they can’t endure it.
“Kuh, what is this…?”
Mii-chan looks around and senses that her mana is being drained, causing her to fall to her knees.
“I, it’s a dark attribute ritual magic [Mana Drain Field]! But I’ve never seen such a powerful effect.”
Yamiyo tells me the effect of this magic field. Because the mana is being sucked out so rapidly, the body enhancement magic is also deactivated, and the body has no power.
“Hahaha. We meet again, Takano Miu. Your mana will be empty in a few minutes. Will you be able to use divine magic like before?”
“Aegir of !”
From the cave depths, a clattering sound of bones is heard, and a robed skeleton with decaying muscle tissues clinging to its cheekbones and pale blue flames in its eye sockets appears. 
The skeletal hand holds the artifact known as Crowley’s Box.
The undead king, Aegir of , who controls the dead and spreads death, is standing there.
“Could this be a trap?”
Mii-chan manages to squeeze out a voice, despite feeling powerless and on the verge of collapsing.
“Exactly. It was quite an effort for us to lead you here unknowingly.”
“And who is behind all this?”
Trembling, Yamiyo manages to stand up with his sword acting as a staff.
“Ah, my apologies. It was me, you see.”
One of the male classmates who collapsed nonchalantly stands next to Egil.
He has an ordinary face, and Mii-chan doesn’t know his name, but with a sneer, his body turns completely black and melts away, revealing a man inside.
“So it was you, Annal… You!”
Yamiyo shouts with hatred, seemingly aware of the opponent’s identity.
“So, you were the ones who stole Menou Marquisate’s new type of magical weapon.”
Elizabeth, who is crawling on the ground, blurts out something strange. A new magical weapon? Is this magic circle related to that?
“Hahaha, if you’re talking about the scrap that was turned into garbage in an instant, then yes, that’s what I mean. I planned to use it for a little experiment, but it was utterly useless trash.”
“Garbage… How much did it cost…”
It seems to refer to the scrap lying over there. It wasn’t in Mii-chan’s memory, but it seems to have been a mid-boss.
So, Menou Marquisate had their magical weapon stolen. I see.
“Hahaha, your mana must be running out by now.”
“This is bad…”
Mii-chan also loses strength and collapses to the ground.
She checks her remaining mana on the status board.