Procas is a powerful warrior and mercenary famously known as "The Grey Despair." He is a man of few words and said to be in the highest class of mercenaries and other mercenaries, including those as powerful as Taakinan fear for their lives when confronted by him.
Procas cares greatly for his daughter who is stricken with deadly disease. He takes on jobs, carrying her with him, in hopes to find a cure for his sick daughter.
Procas was introduced in the story as a mercenary under the service of Chaos hired to kidnap the princess of the Kingdom of Raailon's Keisa Clan, Miss Meira, in exchange for the "fruit of the sacred tree." This fruit is assumed to have the ability to cure his daughter's sickness.
He tried to attack Id and Selena during their meeting to get back his daughter. He was able to defeat Cheyna easily, but was able to get sopped by Selena when she said that Id is the only person to cure her fever called Ice Plan. On hearing this he backed down and consented to help Id if he cures his daughter.
Procas then attacks the Duke Keisa's manour since Id didn't fulfill the promise of healing his daughter Arael. Claymore, the demon lord who Procas had made a contract with tries to persuade Procas to make a new contract with him, that enables him to touch Arael. Lamia warns Id of the new contract and Id interferes to stop it.
Id then shows Arael who is halfway to recovery. He asks him to hold her but on the promise, never again to wield the Demon Aura while Arael is within the Demon Lord's influence.
- Procas is implied to being at the level of a swordmaster. Id, during their first encounter, sensed that he may be at the same level as one of the Fragments of Chaos. He proved to be able to wipe out a group of powerful Orcs and Chimeras, with a single swing of his demonic sword, Dispyle.
- Dispyle is the sword of one of the demon lords who rule over one of the seven regions of the demonic world, Claymore. Claymore is also known as the Lord of Despair and Grey, hinting at the origin of Procas' nickname. Procas was given dispyle after he made a contract with Claymore. It was hinted that Procas may have sacrificed the soul of his wife to make the contract. Dispyle gives him incredible power but at the price of intense, never ending pain. Procas may be able to reduced the agony of the pain if he sacrifices a pure soul, the soul of his sick daughter, to the Claymore but he refuses. His contract with Claymore includes a condition in which the devil must not steal his daughter's soul.