Worrall has been beat around the head a little too much in his life, enough so that much of it is a fog. He vaguely remembers his mother giving him what he needed to survive in the Hive, until she left him...or he left her, not sure which. So, perhaps it's no surprise Worrall got into the game of beating heads himself. Drifting in and out of different crowds, largely indifferent to why they did what they did, Worrall just did what he does best - bash heads.
His one encounter with the City Watch sparked a light - at least a dull one - in Worrall's head. They seemed to care more than just about coin and the next job, there was some higher purpose to what they did. The novelty of this attracted him and, promising to give up his previous ways - or at least bash the right heads - Worrall joined up. He's proud of his new job and perhaps a spark has been lit in his soul, if he can find it.