Either a new anime season,ova,ona,arc,manga series or a continuation to this or something that will connect this story with Mahou Shoujo of the End. There are many things that could be.
I wonder if this means this story is connected to Mahou Shoujo of the End? (I know it’s made by the same author) since they said that the end of the world is happening AGAIN,so now I’m quite intrigued as to what’s to come ....