"The Book of Wisdom."
Betty's voice dropped as she recognized the volume Roswaal had produced.
"That book your ancestor left behind is useless to anyone else. It was keyed to him alone. Anyone else is..."
"I know."
Roswaal opened the book with a gentle motion, the look he turned on Betty softening.
"Though I need to correct you on one point. This book belongs to me."
"What nonsense are you spouting? Even if your name is mostly the same as that Roswaal, you're not..."
Betty had no patience for his claim, dismissing it out of hand.
"He isn't lying. Every word is true."
Reinhard, charged by Gojo with watching Roswaal for any hint of deception, chose that moment to speak.
The words hit the room like a dropped glass.
Betty froze. So did everyone else.
"What's that supposed to mean?"
Gojo scratched his head and turned a baffled look on Roswaal.
"That book is supposed to have belonged to your ancestor, but you're saying it's yours."
"That doesn't add up logically."
"Unless his ancestor came back from the dead after four hundred years, and we all just happened to bump into him at the right moment."
He glanced at Subaru with a grin.
That was the kind of thing light novels pulled, wasn't it?
His head swiveled back, expecting a reaction.
The joke earned him a polite twitch from Subaru and Felt, nothing more.
But Betty, the one person in the room who'd actually known Roswaal's ancestor, wasn't smiling at all. Her face had gone pale with shock and something heavier.
That expression sent a cold little trickle down Gojo's spine.
"Hey. Hey, hey."
"I was kidding, Betty. Why are you taking this so seriously?"
He gave her a small push, fishing for some kind of response.
She didn't move.
The smile on his face wavered. He looked to Roswaal, hunting for an explanation.
And Roswaal, clown makeup on his face, limbs missing, met his gaze and offered a smiling nod.
"Still as sharp as ever, Satoru."
"Though your framing's a little off. I am the same Roswaal who lived with Betty four hundred years ago. The one you were calling my ancestor."
Hearing it from the man's own mouth, the smiles on Felt and Subaru's faces bled away.
"You..."
Gojo sat there stuck, for once short on words.
How was anyone supposed to see that coming?
A throwaway joke had landed square on the truth. It was the kind of thing that made a person want to stop talking for a while.
"If my guess is right."
Betty's voice cut through the silence.
"You used the method Mother left behind, didn't you?"
She'd absorbed Roswaal's revelation without resistance, not a trace of doubt.
"That's right."
Roswaal nodded, crisp and unhesitating.
The two of them traded question and answer, and everyone else sat there with nothing to latch onto.
"Hold on."
"I know we're all reeling, but spare a thought for the rest of us here."
"What's actually going on?"
Felt's patience for riddles had run out.
"A little patience, Miss Felt. I'll walk you through all of it. Please, there's no rush."
Roswaal lifted his teacup, took a sip, and began at his own measured pace.
"My teacher, the one you know as the Witch of Greed, Echidna, was a genius."
"In the field of magic, I'd say no one before or after her has matched her."
"Witch Factor or no Witch Factor, she would've left a name to stand beside the Great Sage's."
His eyes had gone distant, pulled into some private memory.
"Most of the magic known today, my teacher invented."
"And among all of it, there was one spell that stood apart."
"It had no devastating power. It offered no ironclad defense."
"What it could do was transfer a soul from one body to another."
Transfer a soul?
Even Felt, with scant grasp of magic, felt her eyes widen. She understood what that meant well enough.
Swap your soul into a new body when death came knocking. Close enough to eternal life as made no difference.
"Like pouring water from one cup into another. And the spell can be used as many times as needed. A person could extend their life out and out, practically forever, in a subjective sense."
Betty picked up the thread on her own.
"Mother designed that spell for herself, hoping to live a long time."
"Her Authority, you see, wasn't the sort that let her stretch her years the way certain Sin Archbishops can."
"But."
"The spell was extraordinarily difficult to actually cast. In the end, it stayed on paper. And it came with a serious flaw."
"What flaw?"
Subaru leaned forward.
"The caster could only transfer their soul into a body that shared their blood."
Roswaal's voice answered the question directly.
"I remember hearing that the Mathers family has always had only one living member, and none of them live very long. That right?"
Gojo, who'd been quiet a while, raised the point almost conversationally.
"Yes. That's because I was transferring my soul into each successive descendant."
Roswaal's tone didn't shift. Neither did the smile on his face. He had enough composure left to raise his teacup and take another sip.
"You bastard!"
Subaru had never warmed to Roswaal to begin with, and now his fist cracked down on the table. His eyes burned.
Felt leaned back in her chair, disgust plain on her face.
What Roswaal had done was no business of theirs, strictly speaking.
But any person with a working conscience, hearing something like that, was going to feel something shift in their chest.
Even animals loved their young.
And Roswaal?
His children had existed for no reason other than to keep him going.
And the bodies he'd stolen weren't strangers. Each one had been raised, taught, lived with for years.
It was hard for anyone to picture.
Killing a child you'd watched grow for twenty, thirty years. To save your own skin.
Roswaal had done exactly that. Not once. Over and over.
"Four hundred years."
"That would make yours the twelfth generation of the Mathers line, wouldn't it?"
Gojo's voice was level, running through what he'd picked up about the family.
"Yes."
Twelve descendants.
Twelve children killed by their own father.
Even Reinhard's brow had drawn together.
"You did this for Mother?"
Betty had been watching Roswaal without a word the whole time, tracking every small movement.
The Roswaal she remembered had never been a man afraid of death.
If he'd been afraid of dying, he wouldn't have thrown himself at the Warlock of Melancholy all those years ago, fighting to the point of being left half-dead just to buy time.
Something could have changed in the years since.
But up until the moment she'd shut herself in the Forbidden Library, there'd been no sign of it.
If Roswaal hadn't changed, there was only one reason Betty could think of that would drive him to do this.
"Yes."
No hesitation. No hedging.
The answer came clean.
The tightness in Betty's shoulders eased a fraction.
If it was for Echidna, then at least some of it made a kind of sense.
At least the Roswaal in her memory wasn't fully broken by what she'd just heard.
"Hold on."
Gojo rubbed his temple and cut in.
"You were talking about Echidna just now, right?"
Without waiting for an answer, he turned to Subaru.
"You told us before. In the Trial, you saw the Witches' souls, didn't you?"
"Yeah..."
Subaru started to answer on reflex, and then his expression sharpened.
"You want to resurrect the Witches?!"
The words sent Felt bolt upright in her chair, the lingering confusion wiped off her face.
"What?!"
"You want to bring the Witches back?!"
One set of Sin Archbishops running around was already a headache.
A fresh batch of Witches on top of that was the kind of thought Felt didn't even want to chase to its end.
"No, no, no."
"Miss Felt, you've got the wrong idea."
"I'm not trying to resurrect the Witches. Honestly, I wouldn't have the power for it."
Roswaal shook his head.
"My goal from day one has been one thing. Bring my teacher back."
"Four hundred years, I've been preparing for it."
"All this waiting. I was waiting for the right opening."
"You can bring one back but not the others?"
Felt's eyes stayed narrowed on him. She jabbed a finger at Subaru.
"This idiot's many things, but when it comes to this, I trust his word over yours."
"He said he saw all those Witches' souls together, and they looked pretty friendly with each other."
"I know it's hard to believe, but that's the truth."
"The opening I spoke of has arrived. But I'll be honest, even now I don't know exactly how to bring her back."
The faces around the table filled with question marks.
"You know the Soul Transfer spell. Your teacher doesn't?"
"It's not the same."
Roswaal took a beat, considering his words carefully.
"From your perspective, my teacher might still be alive. All she'd need is a suitable body to transfer into."
"But that's not how it works."
"The Echidna Subaru met in the Trial, strictly speaking, is only a residual Spiritual Body. A fragment of her consciousness that lingered."
"First, a Spiritual Body or a stray scrap of consciousness isn't enough to cast Soul Transfer."
"Second, even if her physical remains still existed, preparing a blood-related body for her would be impossible."
"Those two points alone close off any path to using Soul Transfer for her."
"And."
He paused. Something firmer moved behind his narrow eyes.
"What's in the tomb is a Spiritual Body. A Soul Fragment."
"She's my teacher's shadow, my teacher's leftover consciousness. But she is not my teacher."
"The one I want back isn't that. It's the complete, real Echidna of four hundred years ago."
Gojo listened to the speech, watched the conviction burning in Roswaal's eyes, and came up short.
"Is there a difference?"
From where he was sitting, the two sounded functionally identical.
"No. There's a big difference."
Betty turned serious and picked up the explanation.
"A residual consciousness, a Spiritual Body, strictly speaking, is a being without a complete personality."
"If you resurrect something like that, what you get is a broken person. Maybe she wouldn't know what love meant. Maybe her mind would be twisted, drowning in an urge to kill. Maybe she'd be an idiot who did nothing but daydream..."
"But when I was in the Trial, the Echidna I saw seemed pretty normal?"
Subaru raised his hand meekly, the one eyewitness in the room.
He knew he wasn't qualified to hold court on matters of the soul.
But.
He was the only person here who'd actually met this "Echidna."
"With Mother's intelligence, even a residual consciousness could fool you without effort. You're an idiot, remember?"
Betty rolled her eyes at him, unimpressed.
Once the two had finished, Gojo found himself nodding along.
When they put it that way, it made sense.
If you were bringing back someone you loved, you'd want them whole, not a defective copy.
At that point you'd rather not bring them back at all.
"So this opening you mentioned. What is it? And how does the resurrection actually work?"
The curiosity in his voice had edged up a notch.
Resurrecting someone who'd been dead for four hundred years was absurd by any measure.
Granted, his own world had something comparable. The evergreen of the Jujutsu Society, the bearer of the Immortality Technique, a being who'd lived over a thousand years, known to them as Master Tengen.
But simply never dying was easier to accept than coming back from death.
A thousand years alive was impressive, sure.
A thousand years dead, then pulled back?
The scale alone was hard to swallow.
"The opening is this Book of Wisdom."
Roswaal tapped the book in front of him.