Slime Soul (Tensura x Bleach Crossover) (Patreon)

Chapter 17: Face to Face

Fake Karakura Town

Wobbling out from beneath the rubble, I shifted back into my human form and slowly made my way toward Ichigo, who stood in the distance staring at nothing in particular.

The kid looked hollowed out.

After being forced to watch Aizen dismantle his friends and allies one by one, it was no surprise. Even when Urahara, Yoruichi, and his father had entered the battlefield, a revelation that would have shaken him more than it had under any other circumstances, it hadn’t mattered. Aizen had crushed them just as effortlessly, all while Ichigo was kept busy facing Gin Ichimaru.

While all of that unfolded, I stayed hidden.

I observed everything with a critical eye, quietly analyzing the battlefield with Raphael’s help as she finally finished compiling a report on most of the skills I had gained since her last update.

And honestly?

I couldn’t have been happier.

With the exception of Uriel, Lord of Vows, Veldora, Lord of Storms, Elemental Magic, and Summoning Magic, Raphael had successfully recreated every other skill Rimuru possessed by the time he ascended into a True Demon Lord.

That meant I now had access to abilities like Black Flame–Thunder, an Extra Skill refined using data from Yamamoto’s flames, as well as Spatial Domination, among others.

And that wasn’t even accounting for the skills that were uniquely mine.

After extensive refinement using data gathered from the Espada, Raphael had once again done the impossible, evolving my Greed Unique Skill into the Ultimate Skill:

Mammon, Lord of Greed.

My dominion over desire had expanded dramatically. Emotions, impulses, even memories were now within my grasp, supported by sub-skills such as Absorb Life, Control Heart, and Skill Steal.

The surprises didn’t stop there however, as using my Biokinesis skill as a base, she had somehow been able to grant me my fourth Ultimate Skill:

Asmodeus, Lord of Lust.

I now had dominion over the passage of life and death along with allowing me to see the life force of others. A skill that Luminous Valentine would eventually awaken was now mine and it was another Sin Series Skill which were some of the strongest.

Thanks to my wonderful partner, I now held the same number of Ultimate Skills as Rimuru did which was probably the reason she had worked so hard. In an attempt to not be seen as lesser than the Raphael from my memories who served Rimuru.

The silence I received from her was proof enough that I was right which caused her to finally respond.

“You’re just imagining it.”

Chuckling for a bit, I let out a quiet breath as I walked.

‘Hey, Raphael,’ I asked mentally now more relaxed, ‘when do you think would be the best time for me to give you a name?’

She didn’t answer immediately.

That alone told me I’d caught her off guard.

“…The most optimal timing for Master to name Ultimate Skill Raphael, Lord of Wisdom,” she replied at last, a hint of anticipation slipping into her voice, “would be after Master devours Aizen Sousuke and the Hōgyoku.”

I smiled.

‘That’s what I thought too. Guess I’ll be relying on you even more from here on out, partner. And don’t worry about a thing about comparing yourself with the Raphael from my memories, in my mind you are already infinitely better that her because you’re My partner.’ I complimented her putting emphasis on “My” so there was no misunderstanding what I meant.

The response was immediate, but flustered.

“T-Thank you, Master. You can count on me.”

Just as I was about to reach Ichigo, a figure stepped into my path.

Isshin Kurosaki.

Despite his battered state, he stood tall, hand resting on his Zanpakutō as he eyed me warily.

“Who are you?” he asked.

Unimpressed, I raised an eyebrow and glanced past him toward Ichigo, who still looked lost in his own world.

“Hey, dumbass! Stop staring off into space and tell your dad to back off before I punch the shit out of him,” I shouted, loud enough for the teen to hear.

The effect was instantaneous.

Whether it was hearing my familiar voice or just reacting to someone insulting him, probably both, Ichigo snapped toward me with a scowl already forming, only to blink when he actually registered who I was.

“C-Caius!? Where the hell have you been all this time, asshole? I thought you disappeared!” he demanded as he marched over.

Seeing his son’s reaction, Isshin visibly relaxed, lowering his guard and taking a step back, no longer eyeing me with open suspicion.

Raising my other eyebrow, I shrugged and crossed my arms as Ichigo stopped in front of me, clearly waiting for an explanation.

“I don’t remember ever saying I’d be joining this war,” I replied calmly, making him pause and blink. “So why would I stick around when this mess isn’t my problem?”

“You and I had a deal, and I kept my end of it. Orihime’s safe, that’s where my involvement ends.” I shrugged again, nonchalant. “I respect you, and yeah, I consider you a friend. But this war has nothing to do with me.”

Ichigo actually thought about that for a moment, which surprised me, before firing back, “If Aizen succeeds, something terrible could happen to Soul Society, Hueco Mundo, or the World of the Living. Maybe all of them. That makes it everyone’s problem.”

“You don’t know that,” I said, shaking my head, earning a frown from him. “That’s just what you’ve been told. You have no way of knowing whether any of that will actually happen.”

“And for the record,” I added, “aside from Rukia, and maybe Renji, I don’t particularly like Shinigami.”

That one caught him off guard.

Isshin, meanwhile, stayed silent, listening closely, clearly trying to get a read on me.

“And I have it on good authority,” I continued coldly, “that if Soul Society ever figures out what I really am, they won’t hesitate to either kill me or seal me away.”

Ichigo flinched. “T-They wouldn—”

“They would,” I cut in sharply, then let out a slow breath. “Have you not noticed that every major enemy you’ve fought so far—Aizen, the Arrancar, even the Bounts—are problems Soul Society created themselves?”

“They’ve got a lot of skeletons in their closet, Ichigo. And even if you stop Aizen, something else will crawl out of the shadows eventually.” I paused, letting that sink in, hinting at the eventual arrival of the Wandenreich.

“And some of those future enemies? They might even be right.”

Ichigo stayed silent for a moment, weighing my words, before letting out a small sigh.

“You’re right,” he said quietly. “I have no right to ask you to get involved when you’ve already done so much for me and my friends.”

I raised an eyebrow, mildly impressed that he backed down so easily, and was about to respond, when I noticed he wasn’t finished.

“That’s why—” Ichigo suddenly dropped into a deep, respectful ninety-degree bow, catching both me and Isshin by surprise.

“Please help me, Caius.”

My expression stiffened.

“Aizen plans to create the Ōken using the souls of Karakura Town,” he continued, voice tight but steady. “My sisters and my friends are there right now… and I’m not strong enough to save them.”

He bowed even deeper.

“I’m ashamed of myself for even asking,” he said, pouring every ounce of sincerity he had into the words, “but I don’t have any other choice. So please, help me protect them.”

“Ichigo…” Isshin muttered, surprise and pride mixing in his voice.

I stared at the kid for a moment before letting out a slow sigh, then reached forward and lightly smacked him on the head.

“Get up already, dumbass.”

“Does that mean—?” Ichigo asked as he straightened, hope flickering in his eyes.

“Yes, yes,” I cut him off, rolling my eyes. “You’ll owe me a favor later.”

I grabbed his shoulder, spun him around, and shoved him forward. “Now stop wasting time and open a path to Soul Society.”

“Hey! Don’t push me! I can walk on my own!” he snapped automatically—then, more quietly, just loud enough for me to hear, “But… thanks.”

‘So much for waiting until he weakened Aizen with Final Getsuga Tenshō,’ I thought. ‘Looks like I’ll be stepping in a little earlier than planned.’

We made our way toward Isshin.

“Seems you found your resolve,” Isshin said, nodding at Ichigo, who returned it without hesitation. Then Isshin turned to me.

“Isshin Kurosaki. Father of this delinquent son of mine. Looks like I owe you thanks for giving him the kick he needed.”

I nodded once. “Caius Aurelius. Reluctant friend of the Strawberry.”

It said a lot that, despite being called that, Ichigo stayed mostly silent, only quietly grumbling to himself as he opened a Senkaimon. A moment later, we stepped through without looking back.

Running through the Dangai, it only took Isshin a few moments to call for a stop as he noticed that the Kototsu, the train-like entity, was not present. He quickly informed us of his plan to use that fact to our advantage.

“With my spiritual pressure, I should be able to hold back the current for approximately two thousand hours, or three months,” Isshin explained as he pulled several contraptions from inside his uniform. “That should translate to roughly an hour on the outside.”

“While Ichigo trains, I’ll be doing some training of my own,” I said, turning away and moving farther down the Dangai to give them space. “I’ll only spend half that time here. After that, I’ll head to Soul Society to confront Aizen. Use that time wisely, Ichigo.”

“Thanks, Caius. Will do!” Ichigo shouted back, determination clear in his voice.

Hmm. With all the Captains and Lieutenants back in the World of the Living, this would be the perfect opportunity to sneak into the Seireitei and get our hands on some Asauchi. While I doubted they’d be useful in the long run, the metal itself could still be repurposed to construct our own blade.

‘What do you think, Raphael?’ I asked as I finally came to a stop, now well out of sight of the father-and-son duo.

“It would be an excellent test subject,” Raphael replied immediately, slipping into researcher mode. “It would allow us to observe how the metal reacts when infused with Master’s vast magicules.”

That answer made me smile. ‘Good. Then I’ll be sure to acquire plenty for your experiments.’

I sat down on the floor of the Dangai, crossing my legs.

‘By the way, Raphael,’ I continued, ‘is there any way for me to train inside my mindscape like the Shinigami do? I really don’t want to spend a month and a half here doing nothing. This place isn’t exactly suited for large-scale attacks, and I’d rather not draw Isshin’s attention or show him what I’m capable of.’

Raphael was silent for a moment, clearly processing the question.

“It is possible,” she finally answered. “As Master has probably already surmised, with Imaginary Space and his current abilities, Master can create a mental representation of himself here. Would Master like to enter Imaginary Space?”

The way she asked sounded… oddly shy. Almost like she was inviting me into her room for the first time, which I found very endearing.

‘Yes, please,’ I replied, nodding eagerly.

A moment later, I felt my eyes close and my consciousness slip away for a brief instant. When I opened them again, I was no longer in the Dangai. Instead, I found myself in a vast void of near-total darkness stretching on into infinity.

Off in the distance, I could see everything I had collected since arriving in this world, all neatly organized. Even farther away, I could sense the presences of Harribel and her Fracción.

Then the space was suddenly illuminated as a sphere of golden light materialized beside me, and a familiar voice spoke from it.

“I kept them unconscious,” Raphael said, referring to Harribel and her subordinates. “I determined that Master was too busy to explain the situation to them.”

I didn’t respond immediately. Instead, I placed a hand on my chin and inspected the floating sphere that represented Raphael, even circling around it. The light shifted slightly, almost as if reacting to my scrutiny.

“Hmm,” I muttered thoughtfully. “Rimuru’s Raphael, and later Ciel, eventually took on humanoid forms. So I’m curious… what does your human form look like?”

An image flashed through my mind: an impossibly beautiful woman with long blue or white hair and golden eyes.

“…I am still perfecting it,” Raphael replied after a pause, her voice unexpectedly shy. “Master will have to wait a little longer.”

I blinked, then smiled faintly as I realized something. Here, inside my soul, I could sense her fluctuations far more clearly. Every trace of embarrassment, hesitation, and emotion was laid bare.

“I’ll be eagerly waiting, then,” I said softly.

The silence that followed stretched just a bit too long. Raphael drifted in the air, and I could practically feel her discomfort.

“Master is wasting time,” she said suddenly. “Training should begin immediately.”

I couldn’t help but chuckle. We both knew that was a blatant lie. In this space, where thought moved far faster than speech, not a single moment had actually been wasted.

“Very well,” I said with a nod, sparing her any further embarrassment. “Let’s get started on learning how to properly use my new Ultimate Skills.”

=====

Soul Society — Karakura Town

Walking through the streets of Karakura Town, Aizen moved with deliberate slowness, playing a cruel game of cat and mouse as he made his way toward Ichigo Kurosaki’s friends. As he walked, he idly pondered when Gin would finally reveal his hand and attempt to kill him.

At the moment, he was merely killing time, waiting for either Kurosaki Ichigo or Caius Aurelius to appear so he could test his newly awakened power.

So far, the Captains and Lieutenants of the Gotei 13 had proven far too weak to truly challenge him. Even the Captain-Commander had failed to pose a serious threat once his Zanpakutō was sealed.

What Aizen wanted now was simple: to witness the culmination of his efforts in Kurosaki Ichigo, to see just how far the boy’s potential, born of his lineage, could be pushed.

More importantly, however, he wanted to face the strange slime.

Caius Aurelius fascinated him. Unlike any being he had encountered in his long life, Caius defied classification.

Now that Aizen had ascended beyond the limits of both Hollow and Shinigami, his instincts told him something unmistakable.

Caius did not belong to any of the three realms.

The question was how he had arrived here at all.

Aizen came to a brief stop at the scene that unfolded before him. One of Ichigo’s friends stood trembling in his path, gripping a Zanpakutō that clearly did not belong to him. At his side was a strangely dressed, middle-aged man with black hair and a mustache. Behind them, the rest of the group watched in despair.

“What do you want from us?” a dark-haired, athletic girl shouted from the back.

“I merely wish to see whether displaying your corpses at the entrance of the city will push Kurosaki Ichigo’s evolution even further,” Aizen replied calmly as he resumed walking.

Before he could take another step, a woman clad in black with long orange hair appeared in front of the terrified humans. Aizen felt Gin stir subtly at her arrival, though the man masked it instantly.

“Looks like I made it in time,” Rangiku Matsumoto muttered, breathing heavily. She looked haggard, clearly still injured from her earlier battle with Harribel’s Fracción.

Aizen was about to mock her optimism when he froze for a second as a second voice made itself known.

“That’s my line!”

An almost childish voice rang out as a blue slime suddenly appeared to the side, quickly shifting into human form. In its place stood a white-haired young man with glowing golden eyes and a confident smile.

Completely ignoring Rangiku, Aizen focused entirely on the newcomer as his own smile slowly widened.

“It seems we finally meet face to face,” he said smoothly.

“Caius Aurelius.”