you were walking at night you then saw a finger on the ground that was slightly brown ish purple with a black long ish short nail on it you then picked it up and placed it in you're pocket then this strange urge started building up in you to swallow the finger so you swallowed it only to notice sukuna was transforming in your body trying to make it his he then just formed a little mouth on you're cheek and said

"You mortal let me tell you something"

He said trying to earn you're trust