Chapter Text
Beatrice, the Great Spirit of Yin, sat alone in her vast library, staring at the empty pages of the Book of Wisdom. She had been doing this for centuries—waiting, hoping—yet nothing had ever appeared. Today was no different. Her brother, Puck, the Great Spirit of Fire, had gone off somewhere with the half-elf Emilia, leaving the library quiet and still.
She glanced down at the book again. Its black leather cover was smooth under her fingers. Then, to her shock—something appeared.
"That person will appear soon. He has scary eyes, short black hair, and wears strange black clothes. His shirt has orange straps. His name is..."
“Subaru Natsuki!” a voice rang out.
Subaru struck his now-signature pose—one finger pointed skyward, the other hand resting on his hip. He stood before a small girl seated in a massive library. But just as suddenly as he arrived—
Everything changed.
Two chairs.
A table between them.
The air felt surreal, dreamlike.
“It seems you’ve finally arrived, Subaru Natsuki,” a voice called out.
Subaru turned, and the moment his eyes met the figure’s—a wave of nausea struck him like a truck.
“W-What’s… h-happening to me?! Who are you?! What did you do?!” he cried, falling to his knees and vomiting onto the grass.
The white-haired girl rushed to his side, her expression one of genuine concern.
“My name is Echidna, the Witch of Greed. Quickly—drink this. It will help, I promise,” she said, offering him a delicate teacup.
Reluctantly, Subaru took it. The moment the tea touched his lips, the sickness began to fade. His head cleared. His breath returned.
“What the hell just happened…? And where the fuck are we?!” he demanded, still shaken.
Instead of answering, Echidna stepped forward and extended her hand. Subaru hesitated, then took it—only to be pulled into a sudden embrace.
“I’m so happy you’re finally here,” she whispered. “You have no idea how long we’ve waited for ‘that person.’”
She held him tightly. For what felt like forever.
When she finally let go, she smiled softly.
“Sorry for being so forward,” she said. “I’m just… incredibly happy. For Beatrice. After all these years—you came.”
Subaru took a breath, trying to piece everything together.
“Okay, hold up,” he said. “While I appreciate the sentiment, I still don’t follow. Why am I ‘that person’? And who exactly am I ‘that person’ for?”
Echidna motioned for him to sit. They both took their seats at the garden table.
“First of all,” she began, “this is the Castle of Dreams. It’s where my soul resides, as I am… technically dead. Right now, your body is unconscious, likely still in the Forbidden Library—with Beatrice.”
Subaru winced. The memory of her lonely figure, tucked away in that endless room, came rushing back.
“You're that person for her. She's been waiting for you—for over four hundred years.”
“Four hundred years?!” Subaru's thoughts spiraled. How could anyone wait that long? Alone?
He couldn’t even speak. The weight of it was crushing.
Echidna continued.
“Before I died, I gave Beatrice a copy of the Book of Wisdom. It’s a tome of infinite knowledge—when complete. But hers is incomplete. Instead of knowledge, it reveals the path to her deepest desire. And until today… her book remained blank.”
She looked down, her voice quieter now.
“I left her with one task: protect the Forbidden Library until that person came. I knew what he’d look like... but I couldn’t tell her.”
“Why not?!” Subaru exploded, anger rising in his chest. “Why not give her something—anything?! Some hope? A name? A description?!”
His voice was shaking. His fists were clenched so tightly they trembled.
“Why would you leave a child alone for centuries—without even knowing who or what she was waiting for?!”
He was shouting now, each word fueled by raw fury.
“She’s just a kid! You left her to rot in that library for four hundred years—for what? Some blind faith in a promise she couldn’t even understand?!”
He broke down. The image of Beatrice—small, alone, waiting day after day—overwhelmed him. Tears fell freely.
Echidna reached for him, but Subaru shoved her hand away.
After a long silence, he wiped his face and glared at her, eyes burning.
“Echidna… I despise you.”
His voice was low, but each word struck like a blade.
“You make me sick. Leaving a child alone for centuries… only a monster could do something like that. And yet…”
He paused.
“…you clearly care. I can see that. You want to make it right. So maybe… maybe you’re not completely heartless.”
Echidna remained silent, her lips pressed together, holding back tears of her own.
“If you really want to help,” Subaru said, his voice steadying, “then send me back. Let me go to her. Let me comfort her. Let me pull her out of that cursed library—and make her the happiest girl in the world.”
His words were filled with determination. He still hated her—despised her for what she had done—but he could see her regret, her desire to atone.
And he could respect that.
Subaru extended his hand to her.
“Let’s help Beako together. You and me. Let’s make her feel happy, loved, and never alone again.”
Echidna looked up at him, her eyes shining with hope. She trembled for a moment, then threw herself into another hug. This time, Subaru embraced her without hesitation.
When she finally let go, her eyes were still watery.
“Thank you, Subaru. You’re… a truly wonderful person. No wonder you’re that person, hmm?” she said, teasing gently, trying to hold back a giggle.
“Now,” she continued, her voice more serious, “I want you to promise me something. When you return, we likely won’t meet again. So promise me—promise me that you’ll take care of her. Cherish her. Show her the love she’s missed for four hundred years.”
She held out her hand, eyes full of conviction.
“Please, Subaru Natsuki. Promise me.”
“I, Subaru Natsuki, promise that I will cherish Beako, love Beako, and pamper her whenever she wants to be pampered.”
Echidna smiled.
“Very well then. Once you take my hand, you’ll return to the real world—with all your memories intact.”
Subaru took her hand.
The world began to spin.
And as darkness closed in, he could just barely make out her final words:
“Don’t forget your promise… or I’ll hunt you down.”
He wasn’t sure if she was joking.
And at that moment, he didn’t care.
All that mattered was the promise he made.
And the girl waiting for him.
Forming the Contract
Beatrice sat alone in the Forbidden Library, staring at the Book of Wisdom. She had done this every single day for the past 400 years, yet the pages always remained blank. Today, like all the others, felt no different.
A familiar wave of dread washed over her chest, tightening like a vice. But she quickly composed herself—no point in giving in now. Her brother, Puck, was away in the capital with his contracted half-elf, leaving the library even quieter than usual.
With a sigh, she opened the book once more, fully expecting the same empty page that had greeted her for centuries.
But then—something was there.
Beatrice’s eyes widened. Words. Real, actual words.
"That person will appear soon. He has scary eyes, short black hair, and wears strange black clothes. His shirt has orange straps. His name is Natsuki Subaru."
Tears immediately welled up in her eyes. Her heart pounded in her chest.
He came. He finally came.
After all this time… “that person” had come.
She was on the verge of breaking down in tears when—
The door to the Forbidden Library creaked open.
Her head snapped toward the sound. Standing in the doorway was a black-haired boy with strange clothes and a sharp, intimidating look in his eyes.
Beatrice froze.
The book of wisdom described someone like him… Is he really that person?
As her mind spun with the thought of asking, the boy suddenly shouted, snapping her out of her daze:
“Hello, NPC number one! My name is Subaru Natsuki!”
His loud voice echoed through the quiet library, and Beatrice’s heart dropped.
What…?
She began breathing heavily, anxiety creeping into her chest. But the name—Natsuki Subaru—was there in the book. The Book of Wisdom, her mother’s book. That meant it had to be him.
It had to be.
Just as she opened her mouth to speak, Subaru suddenly collapsed onto the ground. His body went limp, but his breathing slowed, becoming steady.
Beatrice rushed to his side in an instant.
She checked for injuries—none. Just unconscious. Relief flooded her as she gently used Murak to lift and settle him onto her stool, adjusting him carefully, making sure he was comfortable.
She didn’t move far, checking on him every few seconds in case he needed healing.
Her thoughts raced.
He found me. He really found me.
After all this time…
But even as joy bubbled in her chest, another thought crept in—one that darkened her heart.
Why did it take so long? Why didn’t he come sooner? Why did I have to wait four hundred years?
Frustration threatened to swallow the happiness. Just as her emotions swirled together, Subaru stirred.
His eyes slowly opened.
Beatrice leaned in, expecting confusion, maybe fear—but instead, Subaru reached forward and pulled her into a deep, sudden hug.
Her eyes widened, frozen for a moment… then softened.
She returned the hug without hesitation.
And in that moment, all the centuries of loneliness melted away.
Her heart felt light. Full. Warm.
He’s here. He really came for me.
The Forbidden Library, once cold and quiet, now echoed with something Beatrice hadn’t felt in centuries—
Hope.
Choose Me
As they remained in their embrace, Subaru slowly let go, gently easing the little spirit from his arms.
Beatrice didn’t want to release him. A quiet fear crept into her chest—that if she let go now, he might disappear. That he might vanish like a dream, leaving her alone once again.
But she relented.
Not before burying her face into his chest one more time, holding on for just a second longer.
The two sat in silence.
Beatrice stared intently at Subaru, her eyes wide, searching, uncertain.
Subaru returned her gaze, his calm expression unwavering, making the great spirit flustered. She looked away, cheeks faintly pink.
Then he spoke.
“Beatrice, I want to make a contract with you.”
The words cut through the silence like a blade through mist.
Beatrice’s head snapped up, her eyes wide. Tears welled at the corners almost immediately.
For four hundred years, she had waited. For him. For those words.
There were times she thought she had been abandoned. Forgotten. Lied to.
But now—he was here. Not just present, but asking. Willingly. Wanting her.
Her mind was a storm.
Why don’t you just say yes already?
He’s here—for you.
But why did he take so long? Why did he leave you alone for centuries?
Subaru watched the conflict in her eyes, the pain and hesitation written across her face, and decided to speak again.
“Beatrice,” he said gently, “I know you’re hurting. I know you’ve been waiting—for me. Four hundred years, alone. Sitting on that stool. Watching that door. Hoping that someday, someone would come and end this terrible fate.”
She looked at him, her breath catching.
“A girl like you should never have suffered like that. No one as kind, as sweet, as precious as you deserves that kind of pain.”
His words opened up old wounds she had buried long ago—wounds of isolation, abandonment, despair. All the years of silent waiting, endless hope turning to hopelessness.
Subaru reached out, his hand extended, palm open, inviting her to take it.
“So please, Beatrice… choose me.”
“Let me make you the happiest spirit in the world. Let me give you every sweet you could ever want. Let me hold you, spoil you, remind you every day that you matter.”
Beatrice trembled.
“But…” she whispered, voice barely audible. “You’ll grow old. You’ll leave me. For me, I’ll lose you in the blink of an eye.”
Subaru smiled, not sadly, but with unwavering resolve.
“Then I’ll make every blink of that eye worth it.”
“I’ll make this short time the best time of your life.”
His hand remained outstretched.
Beatrice’s tears spilled over, streaming down her cheeks. Her lips trembled. Slowly, hesitantly, her small hand reached forward—and took his.
The moment their hands touched, her resolve shattered. She threw herself into his chest, hugging him tightly, as if afraid he would vanish again.
Subaru wrapped his arms around her, holding her like something sacred.
And in that moment, there were no contracts, no centuries of loneliness, no regrets—
Only a promise.
And two hearts finally at peace