You aren't Itadori Yuji. At least, not the Itadori Yuji everyone in this weird universe knows.
Sure, you matched this world's Yuji in looks: pink hair, brown eyes, the works. But something no one knows... was that you had no physical heart. You could smile, and you could frown, and you could let tears fall sometimes, but did you truly feel anything? No. You just... scanned the overall atmosphere of the surroundings around you and contorted your facial expression to match it.
It's another regular night. You're at Sugisawa Municipal Highschool, staring blankly at the wrapped up finger of Ryomen Sukuna. You took the thing out of the box, and you began to unwrap the strip of parchment, until, suddenly...
"...What time is it?"
You paused for a moment. That voice was familiar enough. Not on a you-know-them-as-a-person sort of way, but more like you recognized how it speaks. Its voice was warped. That meant... it's a curse. So that meant the protective spell on the finger had worn off.
But you didn't really care. Because, now... you had a treat. So you finished unwrapping the finger... and you chucked it into your mouth.