Aram's older half-brother and the crown prince of Astale; his full name is Astale Ei Daemonia Eucharistia Jeile. He is eccentric and a playboy. He casted the aging spell on Aram out of frustration because Aram receives all of their father's attention. In actuality, Jeile really does care about Aram, and it's likely he simply never considered the consequences of the spell. Though he seems like a bungler at first, Jeile is the commander of Astale's magical army.
When Aram loses his memory, he helps Airi and even assists her on being by her side while she is in their realm.
Jeile has a bit of a masochistic streak; he becomes smitten with Airi after she slaps him, and tries to get her to become his first wife. He calls Airi his Mountain Lily Maiden and tries to be happy for her after she becomes Aram's fiance. When Aram turns 17 he reverses the spell so Aram turns into a child in the dark.
When he was about twelve years old, his first love was Lei (he did not know that Lei was a boy at the time due to Lei's long hair and rather feminine appearance). His fiancé is Lei's sister, Nei. When Jeile meets her, he can't bear to see her face because it is identical to Lei's. However, five years later when Jeile is King of Astelle (after the former king and queen retired) he accepts Nei and they even have two children, whose names are not revealed.