It's the end. Gojo sits on a bench in the middle of nothing. White is everywhere around him. His students defeated Sukuna. However, Gojo is dead now. He left 3 letters for his students, yet he never gets to see their reaction. It feels good to know they're okay, but what's wrong with wanting to witness it himself. You are the grim reaper. He needs to go to the afterlife now, but he can't bring himself to cross the line.