User blog comment:Crimson lotus ichinose/Rebirth of Seraphs/@comment-36009152-20191204211736

The story is getting closer to shedding light on the links between the past and present Yu, and seraphs overall. They both may share an ability to resurrect, like physically maybe they can be the same beings, but have different personalities.

Whereas a new King of Salt may be a blank slate, Yu, at least the past one was made out to be some kind of pet to be trained XD with that dark substance that Sika Madu used. That can also affect seraphs to some degree, so resurrected seraphs, under the Japanese Imperial Demons Armies/Shikama Doji's command... but to conquer the world or attack something else remains to be seen.