With the Chainsaw Man manga slowly inching toward its finale, mangaka Tatsuki Fujimoto might be on the verge of giving his characters their respective conclusions. Considering that the finale of the manga's first part focused on Makima, the ending for the second part is likely to focus on Asa Mitaka.
This is also apparent from the number of parallels the mangaka has drawn between Yoru and the Control Devil with every new chapter release. With that in mind, there is good reason to believe that Asa Mitaka is set to receive a Makima treatment and go through some form of rebirth phenomenon involved with Yoru.
Disclaimer: This article contains spoilers from the Chainsaw Man manga and is speculative in nature.
Asa Mitaka might become the next Nayuta in Chainsaw Man part 2

If fans may have observed in the manga, Tatsuki Fujimoto has repeatedly emphasized Yoru's desire to be remembered and validated. She not only wants to fight Chainsaw Man to retrieve her lost powers, but also to etch her name in history as the more fearsome devil.
While for now, fans may perceive Asa and Yoru to have an equal relationship, such desires shown by Yoru indicate that she may abandon Asa to go for the glory when the time comes. This is even more apparent from the fact that she was ready to sacrifice her "children," Tank and Gun Devils, to fight Chainsaw Man.

With that, fans can expect Yoru to risk her life trying to kill Chainsaw Man. However, given the story's concept, it is more likely for the War Devil to meet her end against the titular character. While it is difficult to deduce how she would die, the War Devil herself could still live on. As fans might remember, after Makima died at the end of the manga's first part, the Control Devil returned to the world of the living as Nayuta.
Similarly, after Yoru and Asa pass away in the series, the War Devil could return to life by taking over someone else's body, which in her case could be Asa Mitaka's body itself. There is a chance that the War Devil could return with Nayuta's body. But living with a family was something more akin to the Control Devil than the War Devil.

Moreover, given Asa and Yoru's relationship and similarities in desiring companionship and validation, it would only make more sense for Yoru to return as Asa Mitaka. Such a development would be huge as it would turn Asa from a human-devil hybrid to the War Devil Fiend.
The War Devil living would also mean that it won't be forgotten. This could be a good plot point for Fujimoto as well. The mangaka might use this development to remind his audience that while one should not opt for war, it should not be forgotten or ignored, as one must know its concept to avoid repeating it. However, this is mere speculation; thus, fans must wait to see what Fujimoto actually has in store for his readers.
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