The introduction of that eldritch-looking lady does make a case for the
monster tag to appear, for sure. However, further to
Canto Forte point, I think we need to see more of an explicit showcasing of that eldritch lady in appearing more conclusively in further scenarios in the game. Once she gets more screen time added into future versions of the game, then definitely it would necessitate the need for the monster tag to be added. But I think at this point, there isn't enough visibility of her character in-game and/or other monster-like beings to warrant the need to apply the monster tag just yet, but I do see it being added upon future releases of the game.