As soon as the sun had set, Zuko raced out of the palace, trying to put as much distance between the castle and him. He had not seen Katara or his uncle and Bumi still hadn't returned yet. He looked everywhere, but the city of lovers was very hard to navigate.
He finally found them in an alley behind a tea shop. Katara sat against the wall with a perplexed look on her face and he could tell she was confused about something. He noticed that Azula wasn't with them and grew concerned but forgot about that when Katara's eyes widened and she grinned at him. She elbowed Uncle Iroh and he eagerly beckoned Zuko to join them.
When he sat down next to Katara, Bumi whispered something indiscernible to Iroh and he nodded along.
"Well. Thank you for giving me the day off to catch up with my old buddy, but I think it's time I returned to the palace." King Bumi stood up and casually dropped underground.
"I will never understand that man." Zuko said, mostly to himself as Katara shook her head at his words. Remembering that Azula was gone, he asked the pair what had happened.
"I explained the error of her ways and she connected to a version of Azula I haven't seen since her adolescence." Uncle Iroh said matter-of-factly.
"You let her go? She could've been acting and playing on your feelings to get herself out of a mess." Zuko said, horrified that his little sister was let loose on the world once again.
"I would've thought that as well, but I ran into her, and even though she could have fought me and won, she decided to let me go. I saw kindness in her eyes, Zuko. I think that if you can be saved, so can she." Katara explained to him.
"That's different. She is just evil. She killed the Avatar!!"
"You tried to kill him too. Now, I'm not saying that I forgive her for everything she's done, but I do think that she can be saved and redeemed."
"And," Iroh added, "She was a victim of Ozai as well. You may have been the one to get his direct hatred, but Ozai never thought of Azula as his daughter just as he never thought of you as his son. He thought of her as a weapon he could shape and control to his will. She was manipulated by Ozai from a young age and, unlike you, believed Ozai's lies about him loving her, and Ursa being the monster in their story. Let me tell you a story about Azula.
"Before Ursa had been banished, she focused her attention on Zuko and Azula felt as though she didn't love her. This was false, of course, but with the lies Ozai had been feeding her about her mother, she believed it to be true. To make up for the lack of love from her mother's side, she became obsessed with pleasing her father.
"One day the royal family had sat down to eat. Ozai had called for wine. A servant was delivering the wine to Ozai, but he was new to the palace and very young. In his nervousness, he accidentally spilled the wine on Azula. The servant had apologized and Azula had forgiven him. Keep in mind, she was still young and Ozai hadn't gotten to her. But Ozai was furious. Not only at the servant, but at Azula for showing mercy on him. He had the servant imprisoned, but had a lesson in store for Azula.
"The next day, he brought Azula to the dungeon. He had explained to her that mercy was a weak trait and that feelings could affect rational thinking and decisions. He had told Azula that if he ever caught her showing mercy to criminals again, he would make that man suffer a worse fate than he was condemned to and tell the prisoner that it was her idea to increase the severity of the punishment.
"And so, at the tender age of nine, she witnessed her first execution. The servant boy who she made the mistake of showing mercy to. She had believed that it was her fault and became cold and indifferent to the subject's fates, and never made the mistake of displeasing her father again.
Zuko and Katara could only sit in silence as Uncle Iroh explained the horrific story to them.
Zuko swallowed. "I never knew about that."
"Iroh gave him a small, tired smile. "There are a lot of things about your sister that you don't know. Now, let's all get some rest. Tomorrow, we start our journey to the Fire Nation to help both Azula and the young Avatar."
Katara voiced a question that had been bothering her. "What if we are wrong about Azula? What if her insecurities and trauma run deeper than we thought and she can't be saved and she broke the new Avatar the way she was broken?"
A dark shadow passed across Iroh's face. "Then we take the young Avatar from her grasp and hope that we can still save Korra from the ideologies and trauma Azula inflicted on her before it's too late and she becomes a stronger, more powerful Azula. A Dark Avatar."