The Light Novel series is the source material for the adaptation of the Anime and Manga series. The information and terminology on the article will be based on the source material rather than the adaptions.
Isidore (イージドール, Iijidooru) is an archnoble child from the former Veronica faction. He is one of the children that got close to Wilfried in the children's playroom. When Wilfried enters the Royal Academy, Isidore serves as his apprentice attendant.
- It's not addressed why Isidore is appointed as Wilfried's retainer, despite other former Veronica children like Roderick being considered unfit for the position.