Felix paid attention to the mana in his blood and realized it had quickly dispersed itself evenly throughout his blood stream, which meant there was only a trickle in it at any given point. He slowly pulled it out of the tip of his finger and watched as the mana seemed to be pulled evenly from his entire blood stream. He tried to do the same with energy but it was harder to simulate. He flooded his bloodstream with energy then just buffed the muscles in one of his arms. The energy acted the same as the mana had, keeping itself perfectly suffused throughout his body.

"Okay, that makes things really easy. How do I get the mana into my blood from my core though?"

"If it evens itself out, any vein or artery should be fine, but you don't want to bleed yourself out. Ideally something like your lungs where the mana is absorbed into your bloodstream is ideal. You could have it pump into your stomach?"

"I'd still want some sort of flexible tube to do so, I don't want a hard tube in my body at all."

"It doesn't need to be a tube at all though, you could just direct the mana once and make a channel through the dead tissue around there. Shape it into a tube of sorts. Worst case the dead tissue absorbs some of it, but the tissue isn't actually dead otherwise it would rot. It should still be attached to your bloodstream and therefore the mana would likely make it's way there anyways."

"Couldn't I just pour the mana into the tissue around it then?"

"You could, but your stomach is designed to do that now anyways so it's probably faster and safer."

"Alright, well all those designs for channel layouts are useless now I guess."

"I suspect they'll be useful later. I've seen higher tier humans without any blood stream at all, though that is rare."

"I mean yeah, I'll keep them around, they'll just sit in my mind palace."

"What's that?"

"Was a memory technique, now it's a skill. I have a library in my head that stores anything I want permanently."

"How big is it?"

"Not sure, there isn't too much up there right now. Just a few hundred books and other random memories."

"I see."

Guess I can't have the mana cycle in and out of my core then, not sure how to make it go from my heart back into the core. Same thing with energy unfortunately. Damn, I do like this plan though. It's minimally intrusive, I should test casting spells from the mana in my blood stream though just to be sure.

Felix drank the rest of the mana from the canteen and slowly let it suffuse his blood stream. He only had to wait a few minutes for it to be fully absorbed then he pulled mana from his blood to cast a spell, which was unacceptably slow. Felix thought about it for a bit and realized he likely wanted it not in liquid form anyways considering the last time he tried casting a spell with liquid mana. He first relaxed the mana in his blood into a gas which would normally mean it would fall back into the mana dimension. It seemed having it suffuse his blood though, giving it a medium to travel through allowed it to stick around.

Testing the mana with a simple spell cast, he found it was just like casting with his mana pool. Releasing the mana took a miniscule fraction of a second, comparable to how long it was to reach into his pool anyways. It seemed using his veins as channels weren't going to speed up or slow down his casting at all.

Well, I guess I just go for it at this point. Should I drink the mana and move it, or create the liquid mana directly inside my body? Actually I should probably make a container for the mana so I can spin it or do whatever I want with it. Probably out of solid mana. If that's the case, I need to decide on how big it's gonna be ahead of time. Probably as big as I can so slightly less than the thickness of my torso.

Felix took some quick measurements with a thread of mana then began to practice creating a shell of solid mana. The method he came up with was to start from a large marble of liquid mana then grow it into a hollow sphere that he filled with normal mana so he wasn't creating a vacuum. Then he compressed the liquid mana on the outside to solidify it. This created a very thin shell at first, but he could grow it with more mana after it was created. As long as the initial shell was in place and held it's shape, he could go from there to fill it and make the shell thicker.

He also decided to have a small solid tube that came out one side tangential to the shell as the output. That tube would merge with another from the shell for the energy core and would feed into his stomach. He decided he was ok with a small amount of solid tubing because it was very short, with his cores right under his stomach, and they were close enough to his spine that they shouldn't ever be pushed on or bent too much.

He started by creating four canteens worth of liquid mana. Once that was done, he drank the entire contents of one of them and directed all of the liquid mana through his stomach and into the location he had chosen. He was going to have his mana on the left and energy on the right. He slowly expanded the mana like a balloon, filling it with normal mana until it was just the right size. He used some mana to move the useless tissue aside a little but otherwise had no issues. He held it there as he stretched and contorted his body to make sure it wouldn't affect anything, and the result was, he couldn't even feel it.

Stolen from its rightful place, this narrative is not meant to be on Amazon; report any sightings.

He drank another canteen fully and added it to the sphere to make the walls much thicker before he started compressing it piece by piece into a sphere. He felt like he was creating a jigsaw puzzle out of a million pieces where all of the pieces were identical and fused together. The spheres weren't perfectly round but Felix knew from his earlier testing he would be able to mold them a little bit at a time until they were perfect. He formed two spheres next to each-other and connected them with a few simple braces. He then formed a small tube with a dividing wall down the middle and attached it to the top of the two spheres he had created.

Felix slowly moved and positioned the casings for the cores he had created just below his stomach positioning the tube perfectly. The foundation had been set, but he wasn't happy with it being so thin so he drank the other two canteens and used the mana to thicken the walls. He continued to thicken the walls until he was satisfied.

Now the interesting part.

Felix began filling his canteens with mana once again, then drinking them and finally using that to fill the solid core shells he had created. This time he made sure to make the mana as dense as he could, right on the verge of becoming a solid. Once the left side was full he began working on collecting up as much energy as he could and funneling it into the shell on the right side. He had forgotten though, that energy wouldn't leave his body and seemed to exist only within his cells.

Oh shit. Change of plans. Luckily I have a bunch of, currently, useless tissue.

Felix didn't want to cut any of the tissue out as he didn't want it dead, he just wanted it contained. He realized he also probably couldn't funnel the energy into his blood through his stomach the same way mana could.

Unless, can energy exist use mana as a medium the same way it uses cells?

Felix created a thread of liquid mana and touched it to his abdomen then funneled the energy there. He was easily able to move the energy into the mana and directed the thread into his other core. At this point, he had about half of his energy pool and tons of mana to work with. He first experimented with how dense the mana should be to hold the optimal amount of energy. He found that having the mana in a gaseous state right on the edge of becoming a liquid held the most energy. He created a second core out of gaseous mana at the perfect density. Next, he created threads of mana to give something for the energy to flow through when it passed in and out of his core.

The last step before he started up his cores was to figure out a way to keep the mana core filled. His energy core was attached with mana threads to his tissue in multiple places and the spinning of the core should pull the energy into it. The energy should then be balanced and distributed through his body through the single output tube. He was slightly worried he wouldn't be able to pull from the core fast enough, but he would just have to test it and adjust from there. His mana core functioned in the same way, except he wasn't sure how to keep it filled other than to consciously fill it. He didn't have to drink mana to fill it, he could simply pull mana directly into his core from his pool and the ambient, but that was currently a conscious effort. The other issue was that the mana had to somehow become a liquid, hopefully without his conscious attention.

Felix was about to explain the problem to Grim, but got distracted with something he had been wondering.

"Hey Grim, are you male, female or something else? I keep flipping between it and they because I don't really know."

"I'm a book, not sure how I could have a gender."

"Do any of the pronouns sounds particularly fitting to you? Do any of them resonate with you more than the others? You can choose whatever you want, I just want to know what to refer to you as, even if it's currently only in my own thoughts."

"Not really. Wait, important question, what are your sexual preferences?"

"I'm straight, only ever been attracted to women."

"Let's go with male then. I want to avoid the possibility that you ever have romantic feelings towards me."

"I don't think that ever would have been an issue."

"I think it could have. You'll know what I mean later on."

"Well, alright then. Back to the task at hand, how do I refill my core?"

"Do the same thing as your energy core?"

"My energy is just in my tissue, I can run a thread to it and pull the energy. My mana pool is in another dimension, how do I run a tube there?"

"Is it in another dimension?"

"Oh shit, no it isn't, not really. Is that possible though?"

"Possibly? I've never even heard of any of this being done before but I don't see why it wouldn't work."

"I guess I don't even need tubes then, thanks."

Felix reentered a meditation and looked inwards. Mana was theoretically not in it's own dimension, it was just shifted in a spatial dimension. Realistically, he should be able to just run a thread from his current position to the position of mana, running axially in that spatial dimension. The thread would then act as a channel for the mana to move from his pool and the ambient to his core. He could also use the spinning of the core like a pump, at least theoretically. It might also be possible to use tubes instead of threads or threads inside of tubes.

After some experimentation, Felix managed to get a thread that ran into the mana dimension, the problem was that it was very fragile. Large disturbances in the ambient mana, his normal mana pool or even if he just moved his body too quickly, the thread would snap. His next attempt was with solid mana tubes, which worked as he had hoped, but had other big issues. The pulling force from spinning his core was not enough to pull mana through and it only pulled the mana as a gas. His solution was to have a funnel or reverse jet and have the end of the funnel just on the inside of his core. This would cause the mana around the end to effectively pull the mana through the funnel and into his core. If he made the end thin enough, he could almost turn the gaseous mana into liquid mana.

He realized though, that no matter what he did, when he spun the core fast enough, it would be denser the further in the mana was. It was similar to the portable star spell in that the core was the most dense and it grew lighter the further from the core the mana was. The input being gaseous also caused there to effectively be an atmosphere around the core. The gaseous mana acted as a lubricant between the rapidly spinning core and the walls of his casing allowing the core to spin very quickly and undisturbed by friction. The gaseous mana was then also sucked into the core as it spun, like a vortex, compressing it as it was pulled inwards and joined the core. This also worked on his energy core, compressing it as much as possible just from the spinning.

Felix had tested everything outside of his body, now he had to actually start them up. First he made sure they were both about half full as he wanted to minimize potential catastrophes. He held on to and spun the cores right in the center of their casing slowly bringing them up to about half of the speed he was hoping for. He then carefully attached threads of mana to his energy core that would act as sources. He also connected his mana pool to his mana core for it's input. They should pull on their own but he had to start the process, like siphoning gas with a hose. . . . . .