Julius Juukulius (ユリウス・ユークリウス) is Anastasia Hoshin's knight and a member of the Royal Guard.
Julius has yellow eyes and light purple hair that is arranged neatly with a strand hanging down his face. He wears the Royal Guard uniform. When he fought with Subaru, he wore a black suit with blue borders.
As a member of Lugnica's nobility, Julius acts in a proper fashion, always having an air of nobility and conviction. He is also considerate and doesn't forget to show care toward others. He also shows a strict side, giving out accurate assessments of others whether they're good or bad, which is a result of his upbringing as an elite, and in actuality, he believes that he and others can do better than they currently are.
Julius doesn't like those who forget their place, leading him to have bad relations with Subaru for a while. While both have apologized to each other after the battle with the Hakugei, Subaru told him that he still hated him. Julius then told him that he didn't intend to be friends with him. They both became very intimate very quickly during the planning and attacking of the Witch Cult. In the end, Julius directly considered Subaru as his friend.
Currently, Julius has had his name eaten by Roy Alphard, effectively erasing his history from the world.
Julius lived with his family at the Juukulius House. After his father, Klein Juukulius, died, he started to live with his uncle Alviero, who started to take care of Julius and became his adoptive father.
Divine Protection (加護 Kago): Julius has the Divine Protection of Gathering Spirits (誘精の加護), which enables him to see, talk, and be liked by Spirits, though he has to work hard to actually get liked by Spirits.
Spirit Affinity: Julius has a rare innate gift to form contracts with spirits.
Spirit User (精霊使い): Julius was contracted with six Quasi Spirits. They were known as Ia (イア, red/fire), Kua (クア, blue/water)、Aro (アロ, green/wind), Ik (イク, yellow/earth), In (イン, white/Yang), and Nes (ネス, black/Yin). His contract with them was severed when his name was eaten. As Julius is also a knight, he prefers to be called a Spirit Knight (精霊騎士 Seirei Kishi).
Spirit Arts (精霊術): Julius is able to use Spirit Magic with any of his six spirits which afford him a variety of specialties from offense to support like healing.
- Clarista (クラリスタ): Julius imbues his sword with the power of his six Quasi Spirits. Clarista and its different levels are Julius' original magic.
- Al Clarista (アル・クラリスタ): A long range version of Clairsta where this sixfold spell the form of a beam of pure destructive energy.
- El Clausel (エル・クラウゼル): Julius' spirits form a circle around the tip of his sword, which envelopes the surrounding with a pure white light that unleashes a blow that aims to pierce an opponent.
- Nect (ネクト): A high level magic that enables people to share senses within the effect area by connecting their gates. It is considered to be difficult to use, however, In and Nes can use it by pairing Yin and Yang Magic together and tuning the interference of mana between people. If it is too weak, the thoughts won't get through, yet if it's too strong, people won't know where the line between them and other people begins. Performed with In and Nes.
- Fell Goa: Julius calls on Ia and Aro to produce a powerful magical firestorm by combining both Fire and Wind magic.
Magic Swordplay: Julius is highly skilled at sword fighting and can use spirits to further augment or enhance his technique. According to Balroy's notes, based on his strength alone, he could be the second Nine God General of the Vollachia Empire or higher.
Shaknar (シャクナール): Shaknar is Julius' beautiful blue Earth Dragon. Despite forgetting who Julius is, it still accepted him due to its training.
- According to the author, Julius's birthday is July 7 and his birth flower is a Nymphaea, or water lily.
- The name was chosen by his father, Klein Juukulius.