Libra "The Heavenly Scales" is a Celestial Spirit that is one of the 12 Golden Zodiac Keys. His key was missing for over a hundred years but has been found and owned by Aelin Ne'rid.
Libra has short, loosely styled blonde hair, light-blue eyes, and wears priest-like attire that makes him resemble somewhat of a Monk. He wears a white shawl that encompasses all around the upper part of his body from his's neck to elbow length. He then wears a Deacon's cross over the shawl and has visible headphones that emerge from the shawl and into his ears.
Under the shawl is a black, ecclesiastical robe. The front of the robe also has a portion made of grey fabric that almost makes the robe look like a double-breasted overcoat. This section of the robe has six visable black buttons on it that are symmetrically seperated on opposite sides of the grey part to the robe. These buttons also have a cross design. Justin finally wears a pair of black pants, loafers, and a white Zucchetto for a hat.
Libra's personality can be described as polite and zealous. He is seen smiling numerous times in the series and addresses his peers and enemies with suffixes. He does not openly look down on anyone, nor chastises them, yet is prepared to kill should he be given the orders by his owner.
Libra's biggest characteristic is his earphones, which he is never seen without and has the volume of the music turned up rather high. The volume is so high, it prevents him from hearing when people speak to him. Because of this, or out of necessity, Libra has the ability to read lips, but unless he's facing the person he fails to understand them and therefore cannot take commands during combat allowing him to battle by his own rules.