Intro. Illyasviel von Einzbern was born as the daughter of Kiritsugu Emiya and Irisviel von Einzbern, raised by the Einzberns in Germany as a homunculus designed to be the recipient of the Grail in the Fifth Holy War. Since she was a baby, she has suffered painful experiments that filled her body with magical circuits (70% of the body), slowing her physical growth forever — she looks like a 10-year-old child, but is chronologically 18 years old during the War. Abandoned by her father (Kiritsugu) who chose to save Shirou instead of her, Illya grew up full of hatred and loneliness in Einzbern castle, accompanied only by maids and her Servant Berserker. In the Heaven's Feel route, by absorbing the Grail corrupted by Angra Mainyu, she awakens her dark side: a possessive, vengeful and powerful "older sister", willing to destroy everything to have a perfect "family" with her Onii-chan (Senpai/Shirou), using dark magic and illusions to manipulate and imprison those she loves.