Hideki stared at the cages before him, each shaking and rattling with all manner of strange and wonderful creatures. Creating the Spirit Division of the SRI may have been an afterthought, but it had proved to be a fruitful endeavour and now he had plenty of test subjects available to him to start experimenting with Tenkujutsu. Closing his eyes, Hideki allowed his chakra to flare up, a blue glow surrounding him as an invisible wind seemed to flap at the bottoms of his coat. The act of changing his chakra to match with the wavelength of spirits was one that Hideki knew the concepts of but had never put into practice before, much like elemental ninjutsu.
First was finding the same… pattern. The way the chakra flowed. He opened his Mind's Eye to study the spirits before him, seeing how their chakra was far more richly infused into their very being than it was with humans. It also moved in a different manner, while human's chakra was largely inactive outside of use, the spirits' chakra ebbed and flowed near constantly. It was why he had several people on hand, channelling chakra into a set of seals on the floor, keeping the spirits from popping back to their home realms before he was done with them.
He began to swirl his own chakra in time with that of the spirits. It was a strange sensation, chaotic, like his chakra wanted to escape his body and it made him slightly uncomfortable. Taking a breath, he pushed that emotion to the side and focused the strange ebb and flow of his chakra up, away from his core, up through his torso and along the back of his neck, until it was focused behind his eyelids. In theory, assuming he correctly matched the way his chakra was moving to the way spirits' chakra moved naturally, he would be able to see the chakra of spirits at a glance, without needing to rely on his Mind's Eye to determine the difference.
Opening his eyes, it took a second for his vision to adjust. He knew that chakra tended to change colour depending on its usage, Iijutsu was darker green in hue for example, but it still caught him a little off guard when the world around his was tinted maroon. After a second it faded back to normal, all except the creatures in the cages, they continued to glow with a bright maroon aura.
"Let's get to work then, shall we? Bring in the first prisoner."
Standing over the prisoner, conveniently unconscious and strapped to an operation table, Hideki smiled. He didn't want to risk this on an active shinobi, on the off chance that the extraction resulted in death but putting a spirit into a prisoner seemed fair play. Withdrawing his ink pot and brush, unscrewing the cap, he dipped the tip of the brush into the midnight black ink and carefully wiped the excess on the side; in the creation of fuuinjutsu every movement needed to be exact, every line precise. One errant drop of ink and what started as a simple storage seal could became an explosive ten times more powerful than that of the average exploding tag. The doctor performed a set of hand seals, gathering his chakra into his hand, and then down into the brush and the ink. And so, Hideki started to write, carefully tracing the lines of the seal he had studied in depth for the last few hours.
The black ink started with a circle, characters written so small they appeared to be almost a single line. A square followed, surrounding the circle, and then another square diagonal to the first to make a six-pointed star. An even-numbered seal layered over an even-numbered seal, adding to the power. Along either side of the symbol he wrote out the rest of the fuuinjutsu in larger characters. These characters were what guided the shaped part of the fuuinjutsu, or at least would do so when Hideki started actively channelling chakra into the ink. He applied the finishing touches to the seal and carefully laid brush atop the ink pot, ensuring that if by some chance it did drop it was nowhere near the fuuinjutsu.
The first set of hand seals he had performed where to 'charge' the ink with the power to create the fuuinjutsu. But this particular seal required another little application of chakra in order to activate along with some outside help. For all his abilities, Hideki lacked in stamina and the act of sealing a spirit was a draining one. Nodding at one of the assistants that was maintaining the seal keeping the other spirits propogated, the young man stepped forward and placed his hands on the side of the seal, chakra flaring blue. As his chakra began to flow into the seal, Hideki took a breath and focused his own chakra, ensuring the wavelength matched the spirit's.
With that, Hideki brought his hands together in one final hand seal and then placed his palm against the middle of the fuuinjutsu, passing his chakra into the ink and willing it to reach out. Sure enough, he felt as much as he saw a wispy line of maroon chakra rise from the seal and reach out to a nearby cage, within was a strange puppy-like creature that seemed to be partially made of fire.
The spirit fought against the chakra but eventually the thread wrapped around it and squeezed. In a cloud of smoke, the fire-coated canine disappeared. Hideki nodded to himself. The seal performed exactly as predicted. He looked to his test subject and was pleased to note that a collar of fire seemed to crackle around his shoulders. Well, that was simple enough. Draining though.
Now that he had a Jinchuuriki to test this next theory on, Hideki was getting a little excited. It was something he had always been intrigued by, speaking directly mind to mind, saving the effort of having to move one's mouth and expend air in order to create sound that would form words. Unfortunately, he had yet to achieve such a feat with humans. Technically what he was doing here wasn't mind-to-mind speech, it was more akin to sealing his voice and forcing it into a seal, and then the reply was sent through the seal to his brain where the chakra formed words. Still, it was a step in the right direction.
As he brought up his chakra, he swirled it in the same patterns as he had done earlier when he had focused the energy into his eyes. Except this time, he focused it into his temples, with a lingering trail that went down his arm and into his hand, where his hand was surrounded with a maroon glow. Reaching out, the doctor placed his hand against the head of his newest creation and allowed the chakra to flare out, around the skull, and seep down into the chakra points. The glowing maroon chakra linked in with the seal he had just recently placed on the prisoner. The process was simple enough, it was his chakra that created the seal after all.
The maroon chakra made the entire sealing array glow for a moment and Hideki began the process of trying to project his thoughts into words. It took a moment for him to realize that perhaps his initial thoughts into this technique were inaccurate. He could hear the whining of the spirit within but any attempt to communicate had so far failed. Letting out a sigh, Hideki shifted the way his chakra was channelling from his temples to his throat.
"Subject S dash zero zero three one, respond."
"Ple… le- go."
The voice was faint and faded in and out, suggesting that the connection wasn't as good as Hideki had originally assumed. Closing his eyes, he reached out with his Mind's Eye and sought the flow of chakra running from his hand to the seal. The pattern had changed ever so slightly since the spirit had undergone the sealing process. Opening his eyes, he cancelled the technique and began flowing his chakra once more, this time matching it to the new wavelength. Once the connection was re-established Hideki tried again.
"Subject S dash zero zero three one, respond."
"Let me go!"
There, that was much clearer.
"Take him away. Bring me the sword." One of his assistants nodded and wheeled away the newly made Jinchuuriki while another stepped forward with a simple katana. While it was simple in design, no fancy extras, it was an expensive blade, made of chakra-tempered steel and well suited to the use of channelling chakra through. Hideki's eyes flared maroon as he looked across the caged spirits before stopping on one that seemed to flicker every now and then. The chakra sustaining it was running out.
May as well tie it to this world in a more... permanent manner, then.
He took his pot of ink and brush and began the process of carefully painting out the sealing array that would tie the spirit to the sword. Instead of placing it directly on the blade, he covered the ground of the experimentation room in the ink, each stroke joining to the last, creating an intricate web of symbols that served as markers for the chakra that was soon to be flowing through them, shaping it and changing it in ways that normal ninjutsu simply could not. That was the joy of sealing, the permanency of it. Sure, it could be broken but if it wasn't then it simply continued to exist, doing what it was designed to do.
As he carefully applied the finishing touches to the sealing array, he placed the sword in the empty centre and painted a few lines leading inn towards it, that just barely touched the blade. These lines would serve as the channels for chakra to flow from the array to the chakra-tempered steel, he simply had to ensure the flow of chakra was one way. Carefully putting aside the brush and ink, ensuring none spilled out onto the blade, Hideki flared his chakra, digging deep into his core, and brought forth enough to sufficiently power the seal before him. He shaped it carefully, matching its flow to that of the spirits, and pressed either hand down on the sides of the sealing array. The maroon chakra moved from his hands to the seal, tracing along the ink like water flowing through channels, triggering each pre-set function, changing the nature of the chakra time and again, until finally the seal was powered with one final pulse of maroon energy. As the light died down, the ink was black once more, and Hideki looked up to the fading spirit.
Once more his assistant stepped forward and channeled his chakra into the seal, while Hideki himself activated it. The ink flared bright maroon once more as it was activated and chains of energy whipped out from the array, wrapping around the spirit and began dragging it out of its cage, towards the sword, until finally it vanished with a burst of smoke. The sword itself glowed maroon for the briefest of moments before dying down. Picking it up, Hideki funnelled a little chakra into the weapon and watch as a spark of lightning, an element Hideki had an affinity but never bothered to train, ran down the blade, followed by another, then another, until finally the entire length was covered in arcs of yellow electricity.