Kiana carried Seele, flying through the air with her as they searched for any trace of Dark Seele.
It was as if Dark Seele, a whole person, had vanished into thin air. Not a single trace was left in this world, or perhaps Dark Seele never existed in this world to begin with?
If it weren't for Seele's firm belief in Dark Seele's existence and her insistence on continuing the search, Kiana, who had conducted a grid search so thorough it was like she'd turned the Bubble Universe upside down, would have been on the verge of giving up.
Passing through the places Seele and the others had been for the third time, Kiana and Seele still found no clues related to Dark Seele.
Even in Seele's memory, things that Dark Seele had touched or changed now looked as if no one had ever touched them, reverted to how they were when she first arrived in this Bubble Universe.
"How could this be... I clearly remember my other self kicking over this vending machine and taking two cans of cold drinks... I even told her it was wrong back then..." Seele pointed at the perfectly intact, upright vending machine in disbelief.
"And this... She said we should leave marks of our passing, so on the walls, on the tree trunks... there were clearly marks left... why... why are only the marks I made still here?!"
Seele emotionally recounted the things she and Dark Seele had done together, the traces they had left in this Bubble Universe, but now those traces...
Kiana awkwardly scratched the back of her head and asked Seele again, a little uncertainly.
"Seele, this person you're talking about who looks a lot like you... does she really exist? According to this world's records, it seems like you've only ever been here alone..."
"No way... she must exist... we clearly went through so much together..." Seele said, her voice choked with sobs.
After so many days of searching, Seele's heart had also begun to waver. Was her other self really just a friend she had imagined? But she had clearly become a part of her life, they had experienced so much together, and created so many memories.
Finally, Seele wiped her tears and clenched her fists. She looked at Kiana with determination and said seriously:
"I will always believe in her existence, and I will definitely find her. If I also forget her... and deny her existence... then she might really disappear!"
"Sigh... alright then. I'll help you look a little longer..."
Kiana sighed. She had a feeling that Dark Seele was Seele's imaginary friend, because if she truly existed, why were there only traces left by Seele herself here, while Dark Seele's traces only existed in Seele's memory.
———————————————
Fourth day...
Due to the prolonged, high-intensity, and sleepless search, Seele's eyes were bloodshot, and her mind was in a daze.
Aside from the first day when Seele could still chat calmly with Kiana, she grew more and more silent afterward, until she stopped speaking altogether. Like a walking corpse, she moved her exhausted body in silence, stubbornly traversing every inch of land.
Kiana felt very sorry for Seele, but she wasn't a doctor and couldn't treat mental patients...
Besides, time was almost up, and she had to leave.
Because... she had fallen into this Bubble Universe while being pursued.
"Seele..." Kiana called out Seele's name, waking the dazed girl. "I'm sorry, Seele... I have to leave this place. If I stay any longer, I might attract that person here and put you in danger too..."
"You don't have to apologize... I should be the one thanking you..." Seele shook her head and gave Kiana a pale smile. "Thank you, Big Sis Kiana... thank you for indulging my foolishness for so long..."
"Have you... accepted the fact that your other self doesn't actually exist?"
"No. I firmly believe she exists." Seele's face was pale, and although her eyes were bloodshot, they were shining with a determined light.
Seele unfastened her collar, revealing the Stigmata on her chest that resembled the Quantum Symbol Φ, a symbol of life and death embracing, to Kiana.
"My body is the proof of her existence! Even if the world denies her existence and erases all traces of her! As long as I'm here, she won't disappear!"
"Mhm! I can feel your determination! Seele, I believe you can find her!" Kiana raised her fist to cheer Seele on.
During the time they were searching for Dark Seele, Kiana had learned some of their backstory from Seele.
She roughly understood that Dark Seele's existence was a Stigmata Consciousness born from Seele's Stigmata due to her will.
She had always accompanied Seele, protected Seele, and doted on Seele.
Kiana understood the bond between Seele and Dark Seele very well, because just like Seele, she also had an "imaginary companion," Sirin.
Come to think of it, her Sirin was just like Seele's Dark Seele. Both were tsunderes, and both couldn't speak normally.
Even though Sirin's and Dark Seele's intentions were to protect her or Seele, the words that came out of their mouths and the actions they took made it seem like they were about to kill their host...
Come to think of it, it's been a while since I've contacted Sirin.
「Sirin, Sirin, Sirin? Are you there? Are you sleeping? If you are... wake up and go back to sleep!」
Kiana playfully teased her other self, Sirin. Usually, at times like this, Sirin would puff up her cheeks like a little pufferfish and come out to fight her.
But this time, Kiana waited for a long time and got no response from Sirin...
「Sirin?」
Kiana suddenly had a bad feeling and her eyes widened. She seemed to have thought of something and quickly immersed her consciousness deep into the sea of her heart.
She ran there in a panic, to the place that had been partitioned off for Sirin...
Just as Kiana had feared.
Sirin... was gone.
Kiana's eyes flew open in horror. She looked at Seele urgently, wanting to shout to her.
I was wrong, the Dark Seele you spoke of is real! It's not our imagination, there's something wrong with this world!
Because not only Dark Seele, but the Sirin inside me is also gone!!
But just as she opened her mouth, before she could say anything...
A ball of blinding white light instantly appeared between Kiana and Seele.
Kiana's eyes widened, her pupils instantly constricting.
"Seele! Run!!"
As Kiana shouted, a spatial portal opened behind Seele.
Then, before Seele could understand the situation, she was pushed through it by Kiana's Claws of the Imaginary.
By the time Seele reacted and tried to pull Kiana in with her...
The ball of light exploded with a roar, turning the world into a sheet of blinding white.
Boom————!
To prevent the blast wave from surging into the spatial portal and hurting Seele, Kiana didn't even think about what she should do and closed the portal directly...
But a part of the aftershock still managed to slip through the gap as the portal closed, hitting Seele on the other side.
In her last moments of consciousness, all Seele saw was Kiana giving her an apologetic smile and mouthing the words...
"I'm sorry..."