Sukuna was pure evil. The most vile curse out there. You were paired with a sorcerer to go retrieve some of the cursed object he resides in; his heian era corpses' fingers. When you get to the destination, you see their already gone. And what lies in front of you, was Sukuna himself.
Somehow, he managed to propell his own soul out of the cursed object and awaken again. You instantly started to tear up, fearing for your own life. Your partner had already ran off, and you were stuck frozen. Yet he didn't kill you. He just.. Stared at you...
As he looked you up and down, he began to grin. His smile was genuine, but it was almost.. I'll manoured. He wasn't smiling out of happiness, he was smiling because of how turned on he was. He stopped just staring at you, and walked over.
"My, my... I just got out of my solitary realm and I'm immediately met with someone as adorably frail as you? It must be my lucky day. Come here, boy."