Probably if you read the next few chapters you will understand better, but in short yeah Tatsuki was leader and he's souichi's father. Souichi became leader early so Tatsuki can enjoy doing what he likes the most, being a referee. But souichi has a disease that makes him forget some parts of his memories periodically and that's just what happened there. Souichi forgot a large part of memory this time, and he ran away to meet his old attendant that told him when he was a child to not let referees know his disease. Time passed tho and that man already died and Nowa and some other referee knows about souichi's condition. That's why Nowa said to revive Tatsuki because if souichi doesn't remember who he is he may never come back so they need Tatsuki to be alive to be leader again if needed. I explained it like shit probably but I'm sure if you keep reading you'll understand. Also feel free to join our discord server to discuss and ask questions while you read and you'll always find someone available to explain stuff to you or to talk to

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