User blog comment:TheJudicialDoll/White Brick and Black Mourning Dress Speculation/Theory/@comment-6192846-20130725172456

Interesting theory. I am going to have to note that the wiki isn't supporting the notion that Allen is the "counterpart" to the sin of Vanity, or any theory related to it. Allen was touched by the Demon and he is demonstrated to be arrogant, yes, but he does not "share" the sin with his sister. Riliane is always the sole constituent labeled for Vanity in songs and merchandise. Allen is always the one for Loyalty.

Other than little part, I like everything else. You'd have to explain how in-universe, the character was trapped in the mirror though. While the real world symbolism or habit is illustrated, it's a little tenuous to say that just happens. I like the idea, it could connect a character that way.

I would want to ask who the "Rin" character is then, if you think she is connected to Gretel or Riliane in anyway.