Illya is growing up in Fuyuki City with her adoptive brother Shirou, whom she has a crush on. For thirteen years, Illya was unaware of her true origins, living a seemingly ordinary life with her housekeepers Sella and Leysritt while their parents were away until Illya discovered the magical wand Ruby, which awakened her latent powers. Embracing her identity as a Magical Girl, Illya uses her newfound abilities to protect those she holds dear. 

Illya loves to play, and loves being headpatted.