|Appears in:||Fate/kaleid liner PRISMA☆ILLYA|
|Japanese VA:||Katsuyuki Konishi|
|Character type:||Human, Magus|
Darius Ainsworth (ダリウス・エインズワース, Dariusu Einzuwāsu?) is the first head of the Ainsworth family. He has "lived" for one thousand years through the means of a curse upon his descendants that overlay them with a "Conceptual Replacement." His current host is Julian Ainsworth.
Darius displays a bipolar personality switching between calm, sometimes comedic conversation and manic declarations. He is very close with Erika, watching over her and telling her not to leave the estate without permission. He dotes on her for the most part, and her obliviousness to his actions causes her to see him as completely normal. He only becomes angry with her should her actions somehow go against his pursuit of his legend.
Fate/Kaleid liner Prisma Illya 3rei!!Edit
Darius is quite powerful, showing the ability to deflect attacks from Bazett and Kuro easily, catch Excalibur bare handed, and easily dispatch four strong opponents with one Class Card. He uses the unique Noble Phantasms Authoritarian Personalism, Apneic Beauty, and an unnamed dagger from three unknown Class Cards.