Denuab and his brother Dorin Venithon were believed to be born in an Ithorian herdship traveling through Corellian space. The twins grew up in the slum docks of Corellia, most likely due to the herd ship abandoning or losing them.
As a result of their hard childhood, the Venithons grew up with values contrary to the Ithorian norm: they valued power and control instead of peace and life as Ithorians usually did. They felt no guilt depriving people of their possessions, dignity, or life, and decided to become pirates.
They bought a Ghtroc freighter from an Elomin smuggler who had stolen it, with the original documents conveniently "lost." They then registered the Venithon Bandit under both of their names, and during the following years they refitted it with parts stolen from other, newer Ghtrocs; in the end the only original piece that remained was the hull, but the Bandit was the only ship the Venithon Twins ever had.
The ship was usually piloted by Denuab, the more reasonable and educated of the two. Instead of fighting, Denuab only broke the securi-locks and returned to the Bandit while his more aggressive brother performed the boarding itself. However, Denuab usually carried a blaster pistol just in case.
While serving the Fivaran Organization, they worked alongside 46 other pirates trying to ride the Hauler VI, a Censian-class transport. The Venithons then discovered that the cargo of the Hauler was 400 SpecForce Marines of the Rebel Alliance army. The Venithons decided to escape, leaving their colleagues behind to be captured or killed.
They eventually began working for the Hy'thor pirate group, operating in Mieru'kar sector under the leadership of Ompiach. The Venithons served on the leadership council, which in turn served Ompiach, but the Venithons unofficially had a great amount of power on the council's individual members.
In 2 ABY, Ompiach sent the Venithons as envoys to create a treaty among his group and a group led by rival pirate Safonne Pendonn. Although the brothers preferred raiding ships, they accepted the task. Unfortunately, the meeting ended in a battle. During the battle, the crossfire damaged a Rebel freighter with an important cargo. The freighter crash-landed on a nearby planet and the Venithons and their colleagues, trying to show their value, followed it to plunder it.