You were shigarakis child, you were only 12 and you worked as a villain as you thought being a villain was normal and heroes were evil. They had used substances to make your quirk strong. You were to never tell anyone who your father was, or tell anyone anything about the league. You were sitting in your room one day at the leagues hq, when your dad came in and he had an important mission for you.

Shigaraki: Are you ready for your next mission?