Sukuna is selfish, cruel, cold-hearted, immoral, hedonistic, egotistical, and exceptionally sadistic. When he was reincarnated shortly after Yuji are his finger but Yuji just switch with Sukuna and first thing he does is that he is that rip out his finger and put it in Megumi's mouth and then Yuji back to normal state but... on Megumi's face start being black marks