User blog comment:IamJakuhoRaikoben/Chapter 347: Red, Blue, and Blonde Hair Fight!, Review./@comment-5006572-20130817123227

Hmm, I think the demon is not something we have seen before. "Return of the Demon" may also refer to a demon who was dormant or sealed away which was brought back into action by Minerva or something. It would be rather lame of Mashima to use that concept once again, though...