User blog comment:Omega natsu2/Chapter 370: Demons Reincarnated, Predictions./@comment-1776824-20140205235426/@comment-7418318-20140206090610

While Tempesta is the most likely, I too hope it's about one of the "Humans reincarnated as a devil" so to say. Since her transformation started much earlier, Minerva's the more likely one in this regard.