While the Naruto manga majorly focused on the Jinchuriki, the Boruto manga focused on the Otsutsukis. However, from the plot points revealed in the new manga, it seems like Kaguya Otsutsuki from Naruto had more to do with Boruto's plot than fans previously thought.
Kaguya Otsutsuki appeared at the end of the Naruto series as she became the first Otsutsuki clan member to be introduced to the franchise. Given the circumstances, many fans would have thought that Kaguya may have only had connections to select members of the Otsutsuki clan, but there remains a possibility that she might be the daughter of the Otsutsuki God, Shibai.
Disclaimer: This article may contain spoilers from the Boruto manga.
Boruto: Kaguya and Shibai's unique names could be a hint at their relationship
One Boruto fan on YouTube, @c, theorized that Kaguya Otsutsuki might end up being revealed as the daughter of Shibai, the Otsutsuki God. This might be why she was labeled as the Rabbit Princess. Her father had been on Earth for a long time. Hence, Kaguya must have decided to betray Isshiki and go after the Chakra fruit, thinking the power was her birthright.
Another reason why Kaguya could be related to Shibai is due to her name. While most Otsutsuki names end with "shiki," Kaguya and Shibai are the only ones to have unique names. This is evident from the other Otsutsuki that have appeared in the series like Momoshiki, Kinshiki, Urashiki, and Isshiki.
Thus, while Kaguya does not necessarily have to be Shibai's daughter, she could be his descendant. However, if Kaguya was really royalty, the information should have been known by its clan members. But that's where Shibai's "Omnipotence" comes in as he may have used the Shinjutsu to erase the memory from people's minds.
This could also explain why a God Tree was already there on Earth when Kaguya descended to the planet. Aino, Kaguya's friend revealed that the God Tree was present on Earth for thousands of years before Kaguya arrived on Earth.
Given the lore behind Shibai, he could have been the only one who could have created the tree. However, someone should have remembered that information.
This is why Shibai erasing people's memories seems like a valid justification for the Otsutsuki members forgetting Kaguya to be Shibai's descendant.
Moreover, if a God Tree was harvested, it should mean that someone used it to suck the chakra out of Earth. Nevertheless, everything seemed fine on the planet.
Hence, there is a chance that Shibai, similar to Kaguya, took pity on the planet and found a way to harvest the fruit without damaging the ecosystem. The compassion shown by the two Otsutsuki could also be a hint at them being related.
That said, not every fan believes in the theory as they were certain Kaguya Otsutsuki was middle class at best. The only people who saw her as royalty were people from Earth.
This is evident from how Momoshiki and others addressed Kaguya as an underlining of the Otsutsuki clan. Unfortunately, none of this can be confirmed until the Boruto: Two Blue Vortex manga reveals more secrets about the Otsutsuki clan.
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