"She" is not a member of Millennium, strictly speaking. but she is the original vampire upon which all of Millennium's artificial vampires were based.
based their artificial vampires off of her because she carries a
portion of Dracula's vampiric power with her due to the fact that she is
the only person to have had their blood drank by Dracula AND to have
drank Dracula's blood themselves.She is reaveled to be Mina and because alucard dracula did not die she is never free she is destroyed along with the doctor and Walter.