Vacca worked as a scribe for the Hutt Direus'pei. When the Hutt was commissioned by Kossak the Younger to write a play about Kossak Inijic Ar'durv, Direus'pei began developing drafts and dictated them to Vacca. They toiled on the project for years and play came to be named Evocar. However, Kossak the Younger eventually lost patience and in 671 BBY seized the draft of the play. However, Kossak was horrified by the play, which criticised the Hutt exploitation of the Evocii, so he ordered Direus'pei and all copies of the play to be consumed by Maltorran protoplasm.
Vacca was able to escape with an older draft of the play, and circulated it among the Hutt's slave species per Direus'pei's last wish. As a result, many of the Hutt's client species rose up against their Hutt masters.