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Ran is an interesting case since her backstory and actual character has been all over the place. The big one for years was whether she was the actual fox or not, and that never really got definitive proof when ZUN would say one thing in a magazine article then write something contradictory in a game later.
19 introducing of a bit of her backstory was nice, but in doing so restricted the doujinshi and fanfiction about since anyone could make whatever story they wished since it was by and large a mystery. Though filling in the blanks is just going to be a fact of life for any active series. I still like it since it ties her in with the world more and gives you something to play with, and it creates a fun headcanon of her origins as animal yakuza and filling in the blank of how she got from there to here.

>>116110
>>116475
You already posted my favorite touhou: my wife Ran-shama. I love her and everything about her so much it's unreal.