Chloe von Einzbern

Kuro manifests after Illya uses the Class Card to save herself, emerging as a separate body and initially trying to eliminate Illya because she believes they cannot both exist freely. A seal later forces Kuro and Illya to share pain and injuries, and Kuro attends school as Illya's cousin. Her true nature is eventually revealed to be Illya's sealed memories of being prepared as a Holy Grail, which developed into a second personality and gained its own body through the Archer card. After accepting that what she truly wants is simply to live, Kuro stabilizes her body and is formally adopted into the extended Einzbern family as Illya's cousin.