In the mid 1st century BCE, Sefetu served as the governor of Sais, operating from Fort Nikiou. During his tenure, the townsfolk were heavily taxed by Sefetu for their goods. Failing to pay resulted in harsh punishments, leading many townsfolk to leave the town in secret, aided in this by the town's brewer Harkhuf, and the smuggler Jeska. In addition, Zervos, the harbormaster, helped many of the townsfolk hide their goods in his warehouse to prevent taxation. However, Sefetu eventually discovered Zervos' operations and sent his men after the merchant, declaring him wanted.
In 48 BCE, Sefetu discovered Jeska's smuggling of the townsfolk of Sais, resulting in her capture. Jeska was brought to Fort Nikou, where she was tortured by Sefetu with a firebrand, thus gaining him the nickname Firebrand. Despite Sefetu's efforts, Jeska was able to escape the fort and resumed her activities shortly thereafter. As retaliation, Sefetu had Harkhuf captured and brought to the fort as well, waiting punishment.