(Pov Third)
It had been another five years since the clan gathering, and both of the Gojo brothers had spent this time growing, though one more than the other. Despite being born with a powerful restriction, Satoshi had, for some reason, been unable to fully awaken this power of his, and as such, he had only gained a few small boosts outside of his senses. He was stronger than the average child of his age, but amongst sorcerers, that wasn't uncommon, and compared to Satoru, his growth was slow, though that may be an unfair comparison.
Despite this, Satoshi wasn't frustrated as time had gone on; he had grown to further understand his own Heavenly Restriction. While this knowledge was not as obvious, Satoshi had come to understand that each restriction, similar to others, needed a different action to be fully awakened. For Toji, this had been the result of his mistreatment at the hands of the Zenin clan, causing his own restriction to activate early, and for Maki, her awakening was the result of the death of her twin sister, as she would take their cursed energy allowing for the full restriction to activate enhancing her strength enough to destroy nearly the entire Zenin clan.
As such, Satoshi had come to understand that for him to reach his full potential, something major would need to happen, but what exactly he could only guess; if the others were anything to go by, it would be unpleasant.
During this time, though, even without the full power he would get later, Satoshi still trained hard and had begun to incorporate the use of weapons into his combat training. It wouldn't matter how strong he became without cursed energy; Satoshi could never exorcise a curse, which is where the use of cursed tools would need to make up the slack. So with Satoru backing him, Satoshi had nearly unlimited access to the vault of cursed tools possessed by the Gojo clan, though he had his mind set on obtaining a specific few later on.
He wanted tools currently held by Fushiguro Toji, as many of them held incredibly powerful abilities; there were three he could think of in specific terms, though. The first was Playful Cloud, a staff in three sections connected by rings. It was considered a special grade cursed tool, and its power increased based on the user's physical strength, and it contained cursed energy. Most notably, it would later be used by a reincarnated Toji to exorcise the special grade cursed spirit Dagon during the events in Shibuya. The next tool would be the Split Soul Katana, a large katana-style weapon with a fur tsuba and a large blade. It also contained the ability to cut through all physical resistance and cut the soul itself, though it required the user to be able to understand the soul to use its full effects. The best feats of this weapon would be when Maki used it to defeat the cursed version of Naoya. Last but not least was potentially the most powerful of these tools, the Inverted Spear of Heaven. This tool could negate any cursed technique it came in contact with and was used by Fushiguro Toji to nearly kill Gojo Satoru, as it was able to bypass infinity. As a result, Satoru destroyed it after he killed Toji.
Though these were the main tools Satoshi wanted to acquire, they were still out of reach, and as such, he was currently attempting to get used to the tools he had available, and they were more limited than he would have liked. Due to the Six Eyes and even the powerful Limitless technique on its own, the clan had put much less of a focus on acquiring cursed tools, though in this department, Satoshi got some help from his brother.
While a cursed tool tends to be based on a weapon, they are separate objects made specifically with a technique or special ability. On the other hand, there exists the ability to use regular weapons with cursed energy. By infusing their cursed energy into a regular weapon, such as a katana, a sorcerer could create a weapon that could be used to exorcise cursed spirits. This technique is usually used by those with limited abilities in terms of manipulating their own cursed energy. This could lead to the weapon becoming a cursed tool if enough energy is poured into it for long enough.
For his tenth birthday, one of the gifts Satoshi was given was a special katana that had been infused with Satoru's cursed energy for the entire year, leading to it becoming a semi-cursed tool. This would become Satoshi's favorite weapon, and he could often be found training with it during his free time.
The time was soon approaching for when Satoshi would begin to test his skills against actual opponents. He knew things were going to get hectic in a few years. At the age of fifteen, Satoru would join the Tokyo branch of Jujutsu High. There, he would meet and become friends with Geto Suguru and Ieri Shoko, and a year later, Satoshi would join him, and not long after the events of the Hidden Inventory Arc would take place, and Satoshi knew he had one chance to change the entire world if he could become strong enough.