love that you meantioned this!! i actually wanted to include shiu originally, but then decided against it bc blag is at its core a story about isolation, abuse, self-discovery and emancipation. naobito worked hard to ensure toji had no one, not even his brother. its what makes sukuna so special, cause he keeps hanging out with toji despite it all. its tojis only saving grace.
if shiu was there i think sukuna would be pretty jealous lmao hes been in love with toji forever. it would be a pretty funny situationship that either ends with all 3 of them falling in love with each other or it ends in blood. no in between lol