Endless Path : Infinite Cosmos

Using the feedback he received from the girls, Vahn ultimately decided to borrow inspiration from the Heavenly Realm of Danmachi and the Divine Realm of The Transcendental Path to Heaven. This meant, from the moment they were reincarnated, accidental or otherwise, the residents of the Little Garden would have all their powers sealed. They would still able to access them, but, similar to the Gods of Danmachi, doing so would force them back to the Little Garden.

Expulsion from any particular world prevented reentry, and, depending on the circumstances, there was a chance you would be penalized in accordance with your behavior. Inversely, accepting Quests and performing exemplary acts would earn you points towards a number of coveted prizes. Most of these provided advantages towards future reincarnations, but, so long as you accumulated enough points, one of the grand prizes was reincarnating alongside Vahn.

Since time within the Little Garden could be structured in such a way that a single day equated to ten years in the outer realms, it wasn't particularly difficult for Vahn to invest a few days of his time in order to pander to the hardest working girls in his harem. His existence seemed to be intrinsically related to the concept of eternity, so, while it might seem like a waste of time, at least from a purely objective point of view, he didn't particularly mind spending a few hundred years of his eternal life caring for the people that mattered most. He had already been experimenting with having multiple versions of himself existing at different points in time, so, if he worked hard, he might even be able to provide the reward while another version of himself simply meditated for a few days back in the Little Garden.

Though this might sound like he was going to be exceptionally busy, purchasing the Grand Prize outright would require hundreds, if not thousands, of years. There were cheaper methods to obtain it, but, as a countermeasure against people stockpiling points, the girls made it so that most of the cheaper alternatives were related to a lottery. Thus, while it was possible to obtain the Grand Prize earlier, the chances of success were very-near 0.01%. The lots would also be drawn by a completely neutral party, unaffected by skills or Innates related to luck, so, while it was impossible to make sure everything was 'completely' fair, it was as balanced as it could be.

Fortunately, while reincarnating alongside Vahn was among the most coveted prizes, it was not the only item in the Grand Prize category. There were also options along the lines of reincarnating into an Actualized World of your choosing, and, while it wasn't as enviable as spending an entire lifetime together, one of the Grand Prizes included teaming up with Vahn to 'complete a story'. Many of the girls had anime, manga, and video games they had become fond of, so, while it might only be for a few years, they wouldn't mind altering the story or even roleplaying as specific characters so long as Vahn was there to accompany them.

While he had been against entering a Record under an assumed identity, Vahn had opened up to the idea after spending time with Mikoto and sending numerous Templates into Actualized Worlds based on their origins. There were a functionally infinite number of Records where the protagonist was someone who had assumed the role of an existing character, so, while it still made him a little uncomfortable, he wouldn't particularly mind so long as he didn't have parents or siblings to worry about or deceive. After all, even after all these years, there were still times when he imagined what it would be like to live the lives of his favorite characters...

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With everything tentatively decided, Vahn tasked the girls with expanding his territory on the 199th Floor while he invested the vast majority of his time and effort into converting the Little Garden into a Heavenly Realm. He also began working on a prototype of the artifact that would link the internal space of the Little Garden to the outside world. This would ultimately require him to keep it open at all times, but, just as he had done with the Quest Boards in the past, Vahn was mentally prepared to adopt the form of a World Tree himself if it meant completing his objective.

Fortunately, after a number of failed experiments, Vahn, or, more specifically, Rose had figured out a remarkably simple solution to the problem of preserving the girls' Egos and transporting them back to the Little Garden. She was surprisingly against the idea of him transforming into a World Tree, so, after discussing the matter with her sister trees, they proposed the idea of using [Universal Mind] to create 'System Templates' capable of interfacing with the 'Yggdrasil Network'.

Though the notion of creating Templates based on various weapons and artifacts had occurred to him, Vahn had never once considered the idea of creating sapient systems to watch over and guide the people in his charge. This was somewhat ironic considering he was the beneficiary of The Path, and, though she had not always possessed an Ego, Sis was one of the most intrinsic factors behind his success. She not only served as the intermediary between him and The Path, but, even when he was completely focused on other things, she was constantly processing and analyzing any and all information that might be of use to him. In many ways, she was his better half, and, without her, he would have died countless times before finding his footing in one of the safer Records.

Understanding the benefits of having someone like Sis on his side, Vahn conferred with the former to develop System Templates based on his personality and a combination of her abilities. The idea was that they would have all his thoughts and memories, so, even if the girls felt lost or lonely, they would always be able to hear his voice guiding them back.

To prevent any potential 'complications' from arising, Vahn followed Sis' advice by prohibiting the System Templates from developing an Ego of their own. Instead, they would piggyback the Ego of their charge, and, depending on the wants and needs of the person they were looking after, change to accommodate them. This might sound 'unfair' to the Templates in question, but, according to Sis, possessing a True Ego early on would actually be a liability due to the sheer volume of information they would need to process. She even suggested that he generate them without his personality and memories, as, depending on the circumstances, there was a possibility of an overlap occurring if the original Ego sustained catastrophic damage.

Since the entire point of the system was to protect the girls' original ego, not overwrite it with a Template of his own, Vahn ended up following Sis's advice to the letter. This caused the Templates to behave similarly to Memory Fragments, but, after linking his senses with the original, Vahn very quickly understood the reason for Sis' warning. The Template lacked the filter known as Sis, so, the moment he linked their senses, Vahn was momentarily overwhelmed by the amount of information transmitted through the connection. At the same time, time around him had slowed to a crawl, as, for the sake of fulfilling their duties, the Templates in charge of supervising the systems needed to process information far faster than the average quantum computer.

After that little experiment had come to an end, Vahn's appreciation of Sis increased to an all-time high. He knew she worked tirelessly on his behalf, but, experiencing even a few moments of what it was like to be her, his own efforts felt half-baked. After all, from her perspective, his relatively short journey through the Records would equate to more than 400 sextillion years...an incomprehensible number that would break the vast majority of sapient creatures, himself included.

When he first learned this, Vahn actually felt a little mortified, but, before he could even express his guilt, Sis assured him that receiving a True Ego was the greatest blessing she had ever received. She even came out to give him a hug, so, while he couldn't help feeling more than a little apologetic, he did his best to avoid thinking about alternatives to the predicament he had forced upon her. Even if she were only saying it to appease his anxieties, he wanted to believe she was happy, so, at least for the time being, he intended to avoid broaching the subject a second time. This ended up being the correct decision, as, had he pressed any further, Sis was fully prepared to introduce him to all of her 'sisters'...

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For the sake of stability, Vahn ended up shrinking the Little Garden from ten layers to a mere three. The first was obviously the layer containing Rose, his sisters, and their many children, but, instead of a planar world, it was now a full-fledged planet roughly the size of a Red Giant. This meant it had a diameter of approximately one-billion-kilometers, but, considering it would serve as the central hub of countless worlds, this was actually rather modest.

For the foreseeable future, the First Layer would effectively serve as the 'Heavenly Realm' inhabited by the godly pantheon Vahn had inadvertently created. As for the other two layers, the second was basically their version of the mortal world, as, with the exception of a few unique individuals, it was the place where people provided refuge by the Empire would reside. As for its size, it actually had a larger surface area than the First Layer, but, much like the Textures of Gaia, it was able to exist inside the latter without any overlap whatsoever. In fact, you could bore from one side of the First Layer to the other, and, no matter how long you looked, you would never find the Second.

Though he was planning to kick most of the current residents out, Vahn knew it was only a matter of time before he invited others to reside within the Little Garden. Unlike the past, however, he was intending to see how much the residents could grow if he created a situation where they were able to develop without too much interference. With this in mind, he was intending to create a structure very similar to the Tower of Babel, but, unlike its counterpart in Danmachi, his version would punish those who attempted to commit heinous acts within its depths.

Simply put, Vahn wanted to see what kind of society would develop when most of its residents were people who had experienced trauma and adversity. This might seem selfish, but, as someone fated to govern numerous Records and countless worlds, it was better he began accumulating experience sooner, rather than later. The experience he accumulated within his Realm was too biased, so, while some might accuse him of negligence, he wanted to see whether or not Heroes could arise on their own if given adequate stimulus. He also needed a method to deal with the tremendous number of spirits inhabiting the Third Layer, the result of countless monsters brutally slaughtering each other, so, much like the tower back in Danmachi, his own was designed to absorb and purify the negative energy of the deceased so that they might be reborn anew.

The irony that the Little Garden was effectively becoming the same Heaven/Earth/Hell template he observed in countless Records was not wasted on Vahn. Unfortunately, he had underestimated just how much negative energy would accumulate when various creatures were competing for natural resources and trying to survive. This problem had been significantly worsened thanks to the Law of Progress, as, not only did it promote the growth of living creatures, it also supported the evolution of monsters, evil spirits, and, every now and then, beings that greatly resembled demons.

While it was certainly possible for him to kill, purify, expel, or even absorb the energy that had been accumulating within the Little Garden, xenocide wasn't exactly at the top of Vahn's favorite things. If other Gods attempted to erase their creations in an effort to cover up a mistake, he would assuredly disdain and oppose them. Thus, much like the Second Layer, Vahn intended to continue monitoring the Third whilst Urahara and the members of the R&D Division researched methods to control and regulate the flow of negative energy between the two layers. In other words, he was basically doing the job he had initially been assigned in Bleach, but, unlike the members of the Shinigami Research and Development Institute, the members of the R&D Division cared more about the methods used than the results...

(A/N: Alternate Titles: 'What a covetous prize...!','Heph is bae, but Sis is, inarguably, 'best girl'...','TFW the systems you abhorred ended up being adopted for a reason...')