The most Yamato Takeru could achieve was to divide Orochi's soul into eight pieces. Interestingly, one of these Orochi soul fragments was utilized to mend Koyuki soul, a process facilitated by her perfect compatibility with it, even surpassing that of the fragment of Satan's soul.
Hence, her soul gained the ability to manipulate Orochi's soulless body, which lay dormant beneath the entirety of Japan. This is why both the Tokugawa and the Hojo clans support healing her soul. They understand that she was one of the seven deadly sin witches, capable of harnessing power from Satan's soul fragment. Additionally, she is the only daughter of one of the most powerful Miko in Japanese history.
Therefore, the prospect of her becoming the catalyst to wield some of Orochi's power or even control him entirely appears likely to come to fruition. The power to summon cloud, wind, lightning and even calling upon nature calamity is manifesting within her body.
