OKAY, JUST GOT HERE, SORRY ABOUT THAT MORON. IS THAT A PERSON IN A CRYSTAL?
Oh no, there's two of them now.
And of course it is! This is an ABYSSAL ANCHORESS, the previous one stationed at your post and the only one whose body was left presentable. For generations since THE CRADLING, the COUNCIL OF HIGH PROPHETS have had sisters anchored to this post to guard THE LIGHTSEED from those who would abuse its power, though the events that led you here were incredibly unorthodox. You were handpicked.
Obviously, this anchoress won't work for the sacrifice, you don't give a crap about her.