The truth.

According to Sokka, Leo must go to a man who is suspected of killing Sokka's family, maybe even Sokka.

After arriving at the suspect's house, he decides to knock on the door: 

POK, POK, POK.

Nobody answers so knock once more. 

POK, POK, POK.

Someone opens the door, the man opening the door was a man for about fifty years, Leo thoughtfully says: 

Leo: Hello !

Suspect: Hello, who are you? 

Leo: I'm Kento Leo, I'm 23 years old and I'm a surgeon and I want to ask you some questions. 

Suspect: Okay, come in.

Leo enters the suspect's house and starts asking him.

Leo: Do you know anything about the Hitsugi family?  

Suspect: Who? 

Sokka sneaks in and:

Sokka whispers: Ask him something about Rim Ryoko. 

Suspect: I know nothing about the Hitsugi family. 

Leo: What about Rim Ryoko? 

Suspect: I don't know ....... wait ...... I know ..... this name. 

Leo: Can you tell me more, please. 

Suspect: Okay, I'll tell you I really want to remember more of her.

Leo: Okay.

Suspect: I remembered ...... Rim Ryoko ..... she was my first girlfriend. 

Leo in his mind: It works, but I'm not sure that's why Sokka told me her name. 

Sokka whisper: Try to find out more about what he is talking about ! 

Leo: But why did you break up? 

Suspect: How do you know about Rim Ryoko and why did you come to ask me ?!

Leo: Calm down I have no intention, I just ...... Rim Ryoko was ...... my aunt..

Suspect: Oh, I see, but why did you come to me to ask me about the Hitsugi family and Rim Ryoko ?

Leo: When I searched Rim's house, actually,  Hitsugi's house, I found your name written on a piece of paper. 

Sokka in his mind: Impressive, I actually didn't find anything like that, but Leo invents to convince him to spit it all out. 

Suspect: My......name ?

Leo: Exactly, Dominik Tachibana. 

Dominik(Suspect): Yes, this is my name. 

Leo: Now can you tell me why you broke up? 

Dominik: It all started when he met Hitsugi, from the day he left with him because he was rich, I already had a child with Rim, who stayed with them after that, everything was beautiful, until she left with him, we didn't even break up, she just left with her hand in front of me. 

Leo: Okay.

Dominik: From that day on, I thought I would not see them again until my 8-year-old child appeared, Rim didn't even tell him I was his father, after which my child named Rei tells me:

Rei: Dad, please don't let Mommy stay with that bad man. 

Dominik: After that he goes to the dark, I have no idea what that was, I lived in a village far from Noto where Rim lived, I looked down and there was a sheet with Rim's address.

Leo: Are you saying that your child appeared in the village where you lived, when did he live in Noto? 

Dominik: Yes, but I don't understand either because my child was 8 years old when he left with Rim, of course, at the age of 8 he didn't even know that I was his father, theoretically the child should have been 15 years old, but for some reason he remained at 8 years old, because there is a difference between an 8-year-old and a 15-year-old. 

Surprised Sokka listened, because he needed to know about it. 

Leo: Unbelievable !

Dominik: Then I went to the address given and Rei, and her husband, they were both dead on the floor, next to him, there was a man with a child in his arms, but that man, when I looked, was my child, but in his 15-year-old version, he appeared in the village where I lived for 8 years and when he came in Noto he was 15 years old, Rei told me: 

Rei: I was waiting for you, father! 

Dominik: Then he leaves the child who was about 5 years old and commits suicide with a knife, after the kid tells me:

The Kid: Why I'm unhappy ?

Dominik: After that I was really shocked, then a man appears and says: 

The man: From here I take care of Sokka. 

Dominik: Who are you and who is Sokka? 

The man(Getou): Im Getou and Sokka is the unhappy child. 

Dominik: He took his hand and said to me: 

Getou: You can leave, thank you for coming. 

Dominik: Since then I decided to go back to the village I was staying in and stayed for a while, after which I found work and went to Sendai and that's how I got here, I never forgot what happened. 

Leo: Hard to believe, but I believe you. 

Dominik: Thanks, yes and ...... Sokka ..... know, I see you, I knew you were a ghost, but apparently you grew up too. 

Sokka laughing says: Thanks for telling me it's Leo too. 

Leo and Sokka leave Dominik's house and decide to head home.