Sergeant's brother Cedric worked as a Skiffguard at Jabba's Palace, whom he was visiting the day Luke Skywalker turned it upside down. While he stayed for the weekend, Sergeant was very upset by Bane Malar's rumors of his affair with the dancer Yarna. He'd never done anything to Bane, and in fact had never met him before his visit to the Palace. Maybe Bane simply had a problem with his portrayal of a bounty hunter on his hit tv show. Who knows?
On his final day at the Palace, apparently Yarna had also heard the rumors and put her hand on Sergeant's leg. "Are you chicken?" she asked.
Sergeant of course was, and hopped to his feet, and ran for the front entrance. He was stopped short though by the Wookie Chewbacca. Sergeant yelled in his language, "Wait, please, do you have any soap?" Chewbacca then knocked Sergeant back down the stairs and knocked him unconscious.