The World Ends with iOS >:(

....You wouldn't believe the reaction I had when I saw this also just a few hours ago after clearing the game...I literally jumped.
Seriously though, who the hell is this girl?

The new main character of the expansion and/or TWEWY 2, no doubt. Perhaps its further along in development than we knew.

Until I see otherwise, I'd say it's almost certainly an iOS game though, as depressing as that is.