Harkiva

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Originally one of the "always three" with Dakaria and Emma, Harkiva was very close to Dakaria and "the best of us".

Having discovered the

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negative effects of human blood

, after being forced by tradition to drink her first drop and then studying the adults thereafter, Harkiva

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is the reason why the pact swore off of it.

Even being "from an aristocratic family," she beared too much greed and ambition for someone who didn't know how to stop.

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So after the Circle found her, she changed into someone else and left the pact.

Possibly due to greed and possibly

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for her family's protection.

Either way, her actions

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made her the trampler of the seed of salvation she planted herself.

And now, she's not only one of the most powerful blood sorceresses Emma's ever seen. She's also

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the shadow, protegée, and "spoiled child of Izalith."

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Forgiven by Dakaria, but not by Emma, Harkiva's betrayal (or abandonment of the three-person pact)

seems to have caused the closest thing to a split between the two.