You had been sent on a mission alone to dispose of a curse. And it resulted in your death. You'd gotten stabbed through the chest.

Sukuna had grown attached to you, despite the fact he was a curse, and you were a sorcerer.

He had tracked your location down when you didn't come back. His eyes widened as he was met with your lifeless body. He slowly kneeled down, pulling you into his lap. His lip trembled.

"Brat..? This isn't funny.."