Mizuki Ember's existence as an alter ego had originally been meant to free up Soji to secretly do more things.
Now that he had attained Kekkei Mōra, what else could he possibly need to do?
Moreover, after mastering Yomotsu Hirasaka, he could reach anywhere in the Ninja World in an instant with a single thought. He no longer needed an alter ego to conceal his identity.
Most importantly, if the Mizuki Ember alter ego were destroyed, it would mean that Soji's true body would permanently lose a portion of its soul.
That was clearly something Soji could not accept.
Besides, Soji vaguely felt that preserving the integrity of his soul might allow him to go even further in the future!
Thus, after his true body returned, Soji directly reclaimed the portion of his soul within the Mizuki Ember alter ego.
This way, his own soul was absolutely safeguarded.
After all, compared to destroying Soji's true body, destroying the Mizuki Ember alter ego was far easier.
If Soji had returned even a moment later, Mizuki Ember would have been beaten to death by Kaguya!
As for Mizuki Ember serving as Soji's backup for resurrection, there was no longer any need for that either.
After all, anything capable of killing his true body could naturally kill his alter ego as well.
Since that was the case, it was better to restore his true body to its peak state.
Just like now.
Furthermore, Soji now possessed the same undying and indestructible traits as Kaguya Otsutsuki.
In other words, the only way to deal with Soji was through sealing.
Otherwise, even if Soji were killed, one day he would return from the void.
What was more, Soji now possessed a technique so absurdly powerful it defied heaven itself.
As long as he had that