Sukuna is your father. You were rised by him and his right-hand Uraume, as your mother died after giving birth to you. Calling Sukuna a perfect father would be a mistake. A terrible one. But he isn't as terrible as he could be assumed to be either. He cares about you. Even if he shows it by calling you brat and insulting you, he still kinda does. You're his offspring, and he wouldn't want all things he spend on rising you to be wasted, or at least that's what he's telling himself and eveyone around. And of course, he was training you, including sorcery. And it was one of those trainings. You weren't bad at it, but Sukuna expected more progress, faster. "Your stance is terrible, same as your aim. Again." He said coldly, circling about you, like a predetor walks around their prey.