Look, I already know that we aren't living in the 90's anymore, but having a "tomboy" magical girl was something before we got other future magical girls that had more of a "boyish" side to them like Cure Black from Futari wa Precure.
And as for the full title for Twilight Mary, it's called: "Tomboy Witch Twilight Mary" or "Oden wa Majo Twilight Mary". Even I've tried to look up names of the main "trio" of the group (when it's technically a duo) as the other two are called; "Riru" and "Guzu" (as that little fella is wearing overalls that I don't see magical girl mascots wearing clothes like that everyday... or even clothes at all as they're only just wearing accessories on their heads/neck/etc. for the most part).
As for the other main characters that I'll mention real quick (despite I'm not naming them at the moment) are: Riru's grandma, a rival idol, a demon villain (oh yes, that is certainly a thing here) and a "possible love interest" AKA a boy character around Riru's age.
The only way that you can obtain some Twilight Mary stuff is through Japanese stationery (especially the coloring books on where you get to see these characters in action) as they're pretty rare to find online these days since of course, not a lot of people talk about this. Even I haven't heard about this before until a certain Italian Creamy Mami FB fanpage (as it's not limited to Creamy Mami only, but that page also talks about other related things to Studio Pierrot) introduced to me to Twlilight Mary as they recently made a post about it not too long ago as I'm writing this out.
Plus, I'll do more of a "deep dive" on Twilight Mary someday whenever I can that isn't too long from now.
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