Konoe Ayatsuki Mercury

Nine(ナイン), actually Konoe（コノエ）, was a witch, and one of the Six Heroes.

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Nine was a witch and one of the Six Heroes, who taught humans to use magic during the Dark War. She is the mother of Kokonoe. During the Dark War, she created the Nox Nyctores in order to help humans fight against the Black Beast. After the war, she discovered what Terumi's future plans were, and he killed her (this action is why Kokonoe despises Terumi).

She created the Nox Nyctores using human transmutation, a process that requires thousands of human souls. Due to similarities in their appearance and abilities, Phantom may have some connection to Nine. It is notable that in Lambda's arcade mode, Hazama tells Kokonoe that the magical power he used to create Mu belongs to Nine.

Nine's role in the story is further explained in BlazBlue: Phase 0.

Her real name is Konoe, although she hates her real name. She is gorgeous, has long, pink hair and dresses like a witch, naturally. The name "Nine" comes from her being the ninth member of the Magic Guild's Ten Sages. Caelica is her sister, Shuuichirou Ayatsuki is her father, and her mother is deceased. She tells Ragna to beware of Terumi.