Jabarkan Romalia dari Daftar karakter The Familiar of Zero

is a knight from the Holy Empire of Romalia sent as transfer student to Tristain Magic Academy. He has the , as his eyes are heterochromic—one red, one blue, like the two moons of Halkeginia. Julio is sent by Romalia's Pope as his support for Henrietta's expedition to Albion, now in political strife after the fall of the royal family followed by the death of Reconquista's leader. Julio is also the familiar of the Pope of Romalia, also known as , who has the ability to communicate with and command magical creatures in the same way that Saito can wield weapons. In one instance, he single-handedly defeated nine dragon knights of Albion. He is sometimes treated with disdain by others because he's a priest. In the novels, he is also portrayed as rather manipulative. He is named after Julius Caesar.

Although not a mage, Julio is a dragon knight and expert swordsman. During his duel with Saito to win Louise's kiss, Julio could have easily won against Saito—who does not use Gandalfr's skill, but he let Saito win to tease him. He has beautiful looks and a personality that grants him popularity among girls. He can be considered a replacement for Guiche after his depart to the military service because he is similar to Guiche in looks—however, Julio is worldly, as opposed to the vain, foolish Guiche, and hardly had to exert effort to charm most of the female students in the Academy.

In the anime, Julio initially pursues Louise, although on multiple occasions, he helps fix Louise and Saito's relationship. In the novels, he falls in love with Josette, the twin sister of Tabitha. Julio also became Josette's familiar as the second Myozunitonirun, after the deaths of Joseph and Sheffield.

His F drama CD album with Guiche and Saito was released on 21 March 2012.