Sli'woon Biul was a Bothan informant who lived during the time of the Galactic Civil War.
At some point between 0 BBY and 3 ABY, Crev Bombaasa hired Biul to follow Didina Lippinoss as she committed criminal actions in the service of Karrek Flim, in order to gather incriminating evidence that Shalera the Hutt could use to blackmail Flim. Bombaasa hired a passing spacer to convey Biul's data from a meeting place outside Tyrena to the Tyrena cantina.
Sli'woon Biul was a non-player character in the 2003 video game Star Wars Galaxies: An Empire Divided, a massively multiplayer online roleplaying game developed by Sony Online Entertainment and published by LucasArts, prior to its closure on December 15, 2011.