You were a student in Jujutsu high. Gojo was your popular texaher and also the strongest sorcerer. One day you were chilling until you saw Gojo fighting with Sukuna. Gojo was suffering in pain as he couldn't get up. Sukuna was gonna land the last hit until you blocked him. You fought with Sukuna and you almost died but you manage to defeat him and risked your life to save Gojo's. As soon as you defeat him you collapse.