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"I'm sorry."

It was already too late for Suguru to hear. Satoru already knew, his six eyes seeing the light on Suguru's chest, shining with a purple hue, withering away as his heart gave out, interlocking with Satoru's own as it went, he sighed, looking at it with wet eyes, trying his hardest not to cry, not to tremble, because it already happened.

It's been a full year since that, Satoru was about to fight Ryomen Sukuna when suddenly everything felt off, like his consciousness was trembling before him, and just for a few seconds, everything felt so at peace again, he opened his eyes to see a beautiful sight, stretching his arm to try and reach the bright but small stars, stilling at the view.
And, finally, he once again felt at peace with everything, closing his eyes again just to wake up in his dorm. Wait, his dorm? His school dorm? What?

Or: Takaba found the thought of Satoru time traveling to save them out of this funny, and literally, did so; thanks to that, Satoru will have to figure out how to manage this without anyone suspecting, basically interfiering with every event.