Who is Andreios "Rei" and Sebastian from Snakecharm and what is their importance?

Andreios is the leader of the Royal Flight. He is in charge of the group that protects Danica. It turns out that Rei is the criminal falcon for which Syfka has been searching. Rei is really Sebastian, the son of Araceli, and heir to the avian throne. He has taken on Rei's form and has been living as Rei since he and Danica were children and escaped the war.

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