Author's note : When "Inner" Leylin speaks about Leylin (protagonist), he will call him directly by his name since he is a separate entity, although the two are linked by the same goal and interest.
You can see it as the spirit of a zanpakuto in Bleach: it has its own identity but is part of its owner's soul.
That's Inner Leylin. (I've explained it before, but I'm explaining it again to avoid any confusion)
So yes, he can take initiatives himself, the inner version of Willow has already destroyed Willow's memories since he considers it harmful to Willow.
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Bill Cipher's POV
*Bam* Sound of a fist against the barrier around Gravity Falls.
"IT'S NOT POSSIBLE!" I shouted in frustration.
I had been hammering at this damn barrier for hours. It seemed that this cursed kid was right.
I had just traded one prison for another, I couldn't accept that. I had to find a solution, preferably without having to make a deal with this kid.
"Should I find Ford?" I muttered before rejecting the idea.
I thought it was likely he could fix the situation, but he would never agree to make a deal with me. I doubted that torture would really be effective against this man and, anyway, I couldn't sense his presence for a reason that escaped me.
The option left to me was to obtain this damn formula by force from the kid, but I had already tried to some extent.
Torture was ineffective, he even mocked me saying he had experienced worse.
*Snap* Sound of fingers snapping.
"You want to try torturing me again?" Leylin said mockingly after being de-petrified.
"Okay kid, you really think you're in control of the situation?" I said, grabbing him roughly.
"I'm going to find this stupid formula myself if you won't tell me," I declared before rushing into his mind.
...
Leylin Blight's POV (inner)
"This place is surprisingly modern for a mage's mind," Bill Cipher muttered, observing his surroundings.
"That's because everything is in its place, at least until the trash in front of me arrived," I said, observing the reason for the mess I had just cleaned up.
Leylin had lost a lot of memories that were dear to him because of this creature. I intended to fulfill my role in this war.
"Leylin?" Bill said, turning towards me.
"Almost, but it's the same. Now, die," I said, making chains appear to catch Bill Cipher.
"Haha, you're really stupid unlike to other one. I fear nothing here~," he replied mockingly, but his single eye that conveyed a feeling of mockery towards me began to change "emotion".
"What's happening?!" Bill said urgently.
He must have started to feel the weakening of his consciousness.
[#### agrees to allow Leylin Blight to use the ability of the object named "Memory Gun" passively and in a targeted manner in his mind for 1 minute.
In exchange, the individual Leylin Blight will have to give up seeing Sandra forever.
PS: any signature is irreversible]
"You know Bill, the human mind is really fascinating," I said to buy time.
I had to beat him in one minute or ,it would be Game Over since the original should use the Memory Gun to take Bill Cipher with him.
I really hoped this eventuality wouldn't happen. Stan had been able to recover his memories thanks to his habits and his loved ones.
Leylin could do the same, but I don't know if the next Leylin (inner) that would form would really be me.
Not only was my existence at stake because of this bastard in front of me, but I also had to avoid wasting the sacrifice that Leylin had made for this transaction.
I had to use my new temporary powers to erase Bill Cipher's "memories", but also erase his negative emotions that he had against Leylin.
To put it simply, I had to clean up the emotions of hatred that Bill Cipher had for "me", but also any other emotion that could prevent the activation and completion of the Spirit Beast magic formation.
"MISERABLE!" Bill shouted before taking on a monstrous form.
(image)
"You think I haven't understood the situation yet?" he said with a distorted voice.
"You want to 'erase' me, but I can see that the process is slow," he said mockingly.
"I'LL HAVE DEVOURED YOU AND I'LL FIND THIS DAMN FORMULA BEFORE I DISAPPEAR!" Bill shouted, rushing towards me. It seemed that his rage was preventing him from understanding the situation.
I could understand him, he had spent millennia scamming mortals and now, he was being trapped twice.
"It's too late for you, Bill!" I shouted loudly in his direction.
The mental world is a space where imagination is master, that's why I could imagine several dark tentacles emerging from the ground to pin Bill Cipher down.
Bill was struggling against them, but it was useless since I was using my magic to reinforce them, but also the power obtained by SCP-738.
All this was possible using imagination as a base in this particular space, but I could feel that my original was slowly exhausting himself.
After the confrontation with Bill Cipher, he had been able to recover thanks to the petrification that Bill had inflicted on him, but he did not possess infinite magic and I could feel it flowing out.
I decided to accelerate the erasure of Bill's consciousness but also erase any emotion that could be troublesome.
"I can't... lose," Bill Cipher muttered before starting to mutter strange words.
"Shut up, damn triangle," I said, pushing a tentacle into his mouth.
He thought it was a Pokémon game and that I would wait for him to finish his move, he's really stupid.
My work was finished on this side, Bill would soon lose all emotion and memory. He would be nothing more than an empty shell or a vegetable possessing great powers.
"Your turn, Leylin Blight," I said, looking up.
It's hard to manage the inner world of such a crazy person.
...
"It's done, Bill Cipher is under control," I said with satisfaction.
I looked at my hand, it contained the Spirit Beast sealing formation that Willow had engraved to proceed with the sealing ritual.
It was currently different from the original thanks to SCP-738, it could contain Bill Cipher but also preserve me from an energy surplus due to the difference in strength between him and me to inject it slowly into me.
This is with the aim of slowly reinforcing me and avoiding that I explode despite a successful sealing, it's a case that could happen because of the great difference in strength between Bill and me.
"I really hope that the improvements I specified are correctly established, I need them to manage the difference in strength with Bill," I muttered, inspecting the sealing formation.
After finally being convinced, I closed my eyes to concentrate on the Spirit Beast sealing formation and access my soul space.
It only took me a few seconds. I was now in a place with an inconsistent shape with a bleu fire at its center.
"So this is where Willow had to fight to subdue his Spirit Beast," I muttered, looking around.
"You are indeed there," I said, smiling.
In front of me, there was a gigantic Bill Cipher floating aimlessly like a jellyfish in water.
My inner version must have erased all traces of negative feelings towards me and all his memory. He must still have his strength, but his state makes him similar to a living vegetable.
I approached him slowly before using bard magic to put him to sleep, to facilitate the subjugation process.
The situation reminded me of Azathoth who had to be asleep to maintain existence, or when Hypnos had put Alone's soul, Hades' host, to sleep.
I continued to use bard magic by whispering to relax him before beginning the subjugation of his soul. In Bill's single eye, there was a symbol similar to the appearance of my soul that was slowly beginning to appear.
I'm almost done.
...
Willow's POV
"I can't follow you, I have an emergency," I said before leaving the bunker and rushing towards the place where the sounds of several blows were resonating.
"This amount of energy is terrifying, someone is becoming a magus... no, it's much more powerful," I muttered, running towards the location where Leylin must be.
"Professor?" I said, shocked observing the situation in front of me.
"Willow, I don't have much time," he said approaching, he clearly had difficulty moving.
He has the hand that possessed the Spirit Beast sealing formation completely covered with strange patterns. I could just recognize a drawing representing the creature named Bill Cipher on the forearm.
(image)
"You must keep in touch with Ford Pines and Mr. McGucket, but most importantly *cough*"
Leylin started coughing before falling to the ground.
"I..." I wanted to speak, but he stopped me, he surely didn't want me to approach him currently.
He's emitting a really substantial amount of energy, I really hope no one followed me.
A normal human would easily die because of the energy that Leylin is currently emitting.
"We don't have time for a conversation, just listen to the instructions," Leylin said urgently.
I stopped trying to express myself and listened to Leylin's words in silence.
"When I fall asleep, you must absolutely hide my body in a distant past and return to the present. Lilith, who works for the emperor's coven, can help you..." Leylin wanted to say something more, but he fell silent.
He's not speaking anymore and not moving.
It seems he has entered a state similar to sleep but different.
"No... no... NO!" I could only repeat these words looking at Leylin's body, my professor lying on the ground.
I was currently unable to approach to pick him up, I was just too weak and I could feel that I was starting to accumulate damage due to the remnants of the terrifying energy radiation that Leylin had emitted before my arrival.
"Sorry... Leylin, I couldn't help and I can't even approach your body for the moment *sniff*" I said, crying.