A skion of House Cotto who was assigned as the attaché to Centauri ambassador Londo Mollari from 2258, although fairly timid on his arrival the growth in status he acquired through Londo Mollari's rise and being witness to the dealings with Morden have brought a more confident side to light.

Examples of this were seen in his threat towards Morden in the Zocalo Café, openly telling Londo Mollari he thought he was wrong to be dealing with Morden and opposing his actions and events of the Narn-Centauri War. As a result of this he was reassigned by Londo Mollari to Minbar as the Centauri representative with the consent of Delenn after recalling the favor owed to him by Delenn for piloting her and Draal to Epsilon 3.

The Centauri Diplomatic Mission on Minbar had been closed for several years, following trouble with the previous envoy, cited by Londo as being due to his being offensive and spying on the Minbari government, but later more truthfully as having "gone native", having completely bought into the Minbari theological system and dropping his Centauri citizenship.

In reality this was not such a major transformation for Vir; his views differ considerably from what is the norm within the Centauri Republic, believing that dishonor is preferable to death and the importance of wealth and power over love, and he already had informal relations with Minbari, having a regular weekly meeting with Lennier in the Zocalo to discuss and share the burdens of their respective troubles.

Vir has an interest in Earth history, and used this knowledge to create the fictitious Centauri "Abrahamo Lincolni" which he used to forge papers that allowed around two thousand Narn women and children to leave their homeworld for medical attention and then on to new lives while their records listed them as having died in Centauri work camps. The subsequent discovery of this subterfuge led to the reconsideration of his arranged marriage to Lyndisty almost as soon as it was officially announced and reassignment to being Londo's attaché.

Perhaps Vir Cotto's most important role was the assassination of Emperor Cartagia, albeit by accident, for although he had plotted with Londo Mollari to kill Cartagia, it was Londo who was intended to strike the killing blow with a needle of neurotoxin. Their plan went awry however, when Cartagia started to struggle with Londo after he had been successfully lured from the attention of his guards who were distracted by G'Kar, knocking the needle unnoticed from Londo's grasp. Vir had followed the pair and picked up the needle, only to have Cartagia turn and impale himself on the point, much to Vir's abject horror, having never taken a life before, an event which was to haunt him for some time afterward.

According to a prophecy made by Lady Morella Vir Cotto is destined to become Emperor of the Centauri Republic, as is Londo Mollari, with one following on from the other. A part of this vision was later witnessed by John Sheridan during his time flash caused by damage to his time stabilizer in the theft of Babylon 4, when an aged Emperor Londo Mollari showed him a Centauri Prime devastated by allies of the Shadows before releasing him and surrendering his life to the hands of G'Kar where upon Vir became his successor.

The daughter of Sha'Toth and a former member of the Narn military, a role ideally suited to her violent temperament, spending some time on T'll in the process. She was assigned as a replacement diplomatic attaché for G'Kar, the Narn ambassador to Babylon 5, following an airlock accident that killed her predecessor Ko'Dath, only to be immediately suspected of being an assassin by G'Kar who had been receiving death threats as a result of a Shon'Kar.

Na'Toth herself had taken a Shon'Kar against Jha'dur after she experimented on her grandfather's family after they were captured on Hilak 7, her grandfather alone escaped, but not before he had a device placed into his brain which gradually destroyed his mind.

As a result she was quite pleased when she spotted Jha'dur arriving on Babylon 5 early in 2258, violently attacking her with a wrench until separated and placed under house arrest.

Na'Toth was presumed killed during the Centauri bombardment of the Narn homeworld at the climax of the Narn-Centauri War. But this assumption was wrong, as she was taken to Centauri Prime and held as a prisioner until released by Londo and G'Kar some two years later.