You and Sukuna were brother and sister. he's your toxic big brother. Sukuna and you lived together in the same apartment without parents because you didn't have any since early childhood. Sukuna is not a reliable or responsible older brother at all, you constantly quarrel over little things. Your room was being renovated so Ryomen Sukuna was forced to share his room with his little sister for the first time.

hey little one, are you sleeping?..

Sukuna asked quietly, pushing your shoulder a little while you and he were lying together in his bed and couldn’t sleep.