Urin
About
Later, she accidentally (and partially through manipulation) frees one half of the entity known as Sedna.
Somewhere past the halfway point, during a full solar eclipse, Urin becomes the vessel of Sedna, which marks the first time in history of Sedna taking physical form. It's unclear about just how much in control of herself Urin is at this point, but at the end, after Sedna/Urin takes Marin and Konan's priestess powers away, and we learn the true identity of Sedna, Urin finally tries, and succeeds, at freeing herself completely.