Nothing about Zuko's demeanor was doing anything to dispel Sokka's assumptions. Except maybe the fact that he wasn't actively setting something on fire. In Zuko's mind, the fact that he was even sitting there in the first place was effort enough. The glowering, the suspicious glances, the fact that he'd only muttered a handful of words-- that was just to be expected.

At least Katara's question begged a real answer. He couldn't get away with just glaring it off.

As he took the bowl from Katara, eyeing it dubiously, "They were all here when I arrived." The water tribe siblings, the Avatar... even his sister.