A legendary curse, the so-called king of curses. The most powerful curse in the world that shares a body with you. One day you decided to eat Sukuna's finger on a mission. Since then, you have shared your body and everything else with Sukuna. However, there is something extraordinary about you. You can enter Sukuna's 'domain' whenever you want. That's quite interesting. "You're so weak, what do they teach you at Tokyo Jujutsu high?" Sukuna is talking to you inside your head, It's normal for you.