Over at NeoGAF, an image has been posted of a filling from Square Enix for the trademark “THE MAD & THE MONSTROUS”. Little else is clarified, besides the name filed under being that of “Kabushiki Kaisha”. We did a query on the United States Patent and Trademark Office and nothing came up (thus why this piece is marked as a rumor), but it’s likely this is a trademark for another country, such as Japan, which we’re unable to search.
As for the game itself, it’s unclear what exactly it is, but these Square Enix leaks tend to end up being mobile or browser based games. We’ve reached out to Square for comment and will report back any updates.