Zuko had been ready to reach out and embrace the waterbending peasant--terms that he now found endearing when used in regards to her, no longer mocking or demeaning--but she turned and he looked over her shoulder and saw why. He felt the urge to sit back down upon the ground and turn his head away and continue to ignore him, but held back. This time, he had the advantage and he just dared the professor to anger a master waterbender and a half-demon seer. In fact...
He suddenly stepped out to the side, brown eyes narrowed and a sneer set on his lips. "You want to see bending?"
The professor's eyes lit up. "You're going to bend for me, little prince? If I knew that a visit from your...friends was all it took to inspire you to do so, I would've had them brought here ages ago."
"I told you," Zuko shouted with an edge he'd managed to keep at bay recently, "with the sun gone, I can't bend! ...but she can." He turned to Katara and nodded.