Liz and Averil.
Characters or something. These two are arguably my most interesting (or at least I think so).
Liz here has Disassociative Identity Disorder. Averil being her other personality.

Basically:
Liz is more withdrawn, shy, and a little bit mentally unstable (and has glasses).
Averil is more outgoing, social, and willing to take risks.

Kind of like a coin. It's one character, but has two different sides.
There is no deep symbolic meaning to this at all, don't let anyone tell you otherwise.