Honestly my theory is that any Dante and Ayin parallels can be chalked up to Limbus Company actively grooming Dante to fulfill the role Ayin had, both as a manager and as the one tasked with resolving the issues of the Sinners/Sephirot to allow them to grow, not because they're actually Ayin (besides, you would think Carmen would have much more of a reaction to Dante if that's the case). Just like how they're attempting to replace LobCorp (and with Dias possibly funding the entire operation, their purpose is actually to replicate the extent LobCorp, through turning Garion into Binah, the Seed of Light project, and the entirety of the Library, was able to defy the Head), I assume LCB is basically their attempt to recreate the power and influence that Ayin and the Sephirot had (with the Golden Boughs possibly allowing for a second rendition of WNDD if the theory about them being Carmen's nervous system is true) which is why the Sinners are basically given a blank cheque and a whole ass Colour Fixer to accompany them (even if they're not able to use any of it whatsoever, as them working their way up from rock bottom is basically the point)
And no, I don't believe they're X either, considering even Vergilius (a Colour Fixer) believes pre-amnesia Dante to be some big shot, and X is just. Some Guy. But since Dante is to their former self who X is to Ayin, I wouldn't be surprised if that's why Dante is paralleled to X as a result. Considering how they're literally Sinner #10, X; the X of the LCB
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