Well Ravus is latin that's right, but it means to me "grey" or "grey-yellow".
So why grey?
Because he's neutral (black-Lucis/white-Niflheim)?
He's also wearing a black+white cloth = grey or based on his old versus cloth it was completely grey.
Also have a high res poster: (Now I need the high res of those characters^^)
It's not a crystal what Luna is holding, it's the ring.^^
It really has a special meaning to the story.
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