Ring Eyes

Ring Eyes are a very legendary feature that only one being can have in existence at one time. They are currently held by Gray.

Description
So in order to have a new holder, the previous one must either die or lose the eyes' abilities (Become blind, losing the eyes, etc.).

The holders of the eyes can oddly be confirmed by having their last name being "Gray" and their first name beginning with "A". It is unsure why exactly it is this specific, but it may relate to the very first holder's full name.