Tu'Pari is a Narn and member of the Thenta Makur. In 2258 he was hired by Du'Rog to kill Ambassador G'Kar, one of his enemies in the Kha'Ri, upon his death. Like all members of the assassin's guild, he left a black flower (or "death blossom") near one of his intended victims so they knew to get their affairs in order.
Tu'Pari assumed the identity of a diplomatic courier en route to Babylon 5 after killing him. He gave G'Kar a message from Du'Rog which explained that Du'Rog had hired an assassin to kill G'Kar, then managed to leave his calling call black flower on G'Kar's pillow during the night while he slept. After keeping G'Kar in suspense, killing the bodyguard the Narn hired, and misleading him into thinking that his new ambassadorial aide Na'Toth was the assassin, Tu'Pari finally showed his hand, incapacitating G'Kar and removing him to an isolated location on the station. There he preceded to torture the ambassador, trying to get him to cry out for mercy before killing him.
Na'Toth however realized what was going on and prevented the death of G'Kar. Knocking out Tu'Pari, they left him unconscious until after the appointed time agreed to by the assassin and the Thenta Makur for G'Kar's death. G'Kar deposited money into Tu'Pari's account to make it appear that he had been bribed into not killing G'Kar, scandalizing the Thenta Makur.
Upon hearing this, Tu'Pari realized that his life was all but over as the Thenta Makur is not a forgiving organization.
Tu'Pari's sole appearance was in The Parliament of Dreams.