A Touhou character.
A girl living in the outside world with the ability to see borders of any kind, including the one which separates our world from Gensoukyou. Along with Usami Renko, she is the member of an Occult Club with the secret purpose of finding a way into Gensoukyou.
Due to both characters having boundary-related abilities, as well as a degree of visual resemblance, fan theories abound about a possible connection between Maribel and Yakumo Yukari, with some even going so far as to suggest that they are somehow the same person.
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